Patent Application
20220379262
The present invention relates to methods, compositions and devices for efficiently capturing carbon dioxide from the atmosphere and regenerating the sorbents used to capture the carbon dioxide.
Anthropogenic greenhouse gas emissions are the leading cause of global warming, with carbon dioxide as the primary contributor coming from both point sources and distributed emissions. While post-combustion carbon capture is an effective near-term mitigation strategy for combating carbon dioxide emissions, negative-carbon technologies must be employed in order to avoid excessive carbon dioxide emissions as one third of carbon dioxide emissions come from point sources and the scale-up of technologies for post-combustion carbon capture and storage are challenging and have progressed slowly.
Net emissions of carbon dioxide (CO2) including not only household requirements met by energy services, transportation, land use, agriculture, but also industrial production is a critical component in stabilizing global mean temperature. Some energy services such as heating and cooling whether household or industrial in nature may be obtained by generating electricity from renewable energy sources. However, industrial processes that necessarily utilize and release carbon dioxide into the atmosphere present a problem with serious consequences. Additionally, carbon dioxide is a product used widely in industry for a wide variety of purposes such as in the food and beverage and agriculture sectors.
In an embodiment of the present invention, removal of carbon dioxide from the atmosphere is carried out using DAC with a sorbent and release of the carbon dioxide using microwave (MW) irradiation to regenerate the sorbent. In an embodiment of the present invention, removal of carbon dioxide from the atmosphere is carried out using DAC with a poly amine sorbent and release of the carbon dioxide using microwave (MW) irradiation to regenerate the poly amine sorbent. In an embodiment of the present invention, removal of carbon dioxide from the atmosphere is carried out using DAC with a poly amine sorbent and release of the carbon dioxide using radio frequency (RF) irradiation to regenerate the poly amine sorbent. In an embodiment of the present invention, the poly amine sorbent can be polyethyleniemine (PEI). In an embodiment of the present invention, the PEI sorbents can be grafted or loaded onto solid supports. In an embodiment of the present invention, the solid supports can be cellulose acetate, gamma alumina, titania or functionalized cellulose acetate silica dioxide. In an alternative embodiment of the present invention, the poly amine sorbent can be branched PEI functionalized cellulose acetate silica dioxide sorbent material. In an embodiment of the present invention, the MW irradiation energy consumption can be monitored to optimize the time taken for efficient regeneration of the poly amine sorbent and thereby increase the removal of carbon dioxide. In an embodiment of the present invention, a MW swing technology utilizes laminar-flow contactors with solid-amine sorbents coupled with a MW swing desorption (MWSD) step. In an embodiment of the present invention, a continuous mechanism for moving the contactors through the MW desorption cavity can be employed. In an alternative embodiment of the present invention, a process for moving the resonant cavity and waveguide around the sorbent material can be employed.
This invention is described with respect to specific embodiments thereof. Additional aspects can be appreciated from the Figures in which:
The transitional term “comprising” is synonymous with “including,” “containing,” or “characterized by,” is inclusive or open-ended and does not exclude additional, unrecited elements or method steps.
The transitional phrase “consisting of” excludes any element, step, or ingredient not specified in the claim, but does not exclude additional components or steps that are unrelated to the invention such as impurities ordinarily associated with a composition.
The transitional phrase “consisting essentially of” limits the scope of a claim to the specified materials or steps and those that do not materially affect the basic and novel characteristic(s) of the claimed invention.
A metal comprises one or more elements consisting of lithium, beryllium, boron, carbon, nitrogen, oxygen, sodium, magnesium, aluminum, silicon, phosphorous, sulphur, potassium, calcium, scandium, titanium, vanadium, chromium, manganese, iron, cobalt, nickel, copper, zinc, gallium, germanium, arsenic, selenium, rubidium, strontium, yttrium, zirconium, niobium, molybdenum, technetium, ruthenium, rhodium, palladium, silver, cadmium, indium, tin, antimony, tellurium, cesium, barium, lanthanum, cerium, praseodymium, neodymium, promethium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, lutetium, hafnium, tantalum, tungsten, rhenium, osmium, iridium, platinum, gold, mercury, thallium, lead, bismuth, polonium, francium and radium.
A plastic comprises one or more of polystyrene, high impact polystyrene, polypropylene, polycarbonate, low density polyethylene, high density polyethylene, polypropylene, acrylonitrile butadiene styrene, polyphenyl ether alloyed with high impact polystyrene, expanded polystyrene, polyphenylene ether and polystyrene impregnated with pentane, a blend of polyphenylene ether and polystyrene impregnated with pentane or polyethylene and polypropylene.
A polymer comprises a material synthesized from one or more reagents selected from the group comprising of styrene, propylene, carbonate, ethylene, acrylonitrile, butadiene, vinyl chloride, vinyl fluoride, ethylene terephthalate, terephthalate, dimethyl terephthalate, bis-beta-terephthalate, naphthalene dicarboxylic acid, 4-hydroxybenzoic acid, 6-hyderoxynaphthalene-2-carboxylic acid, mono ethylene glycol (1,2 ethanediol), cyclohexylene-dimethanol, 1,4-butanediol, 1,3-butanediol, polyester, cyclohexane dimethanol, terephthalic acid, isophthalic acid, methylamine, ethylamine, ethanolamine, dimethylamine, hexamthylamine diamine (hexane-1,6-diamine), pentamethylene diamine, methylethanolamine, trimethylamine, aziridine, piperidine, N-methylpiperideine, anhydrous formaldehyde, phenol, bisphenol A, cyclohexanone, trioxane, dioxolane, ethylene oxide, adipoyl chloride, adipic, adipic acid (hexanedioic acid), sebacic acid, glycolic acid, lactide, caprolactone, aminocaproic acid, aziridine and or a blend of two or more materials synthesized from the polymerization of these reagents.
A ‘contactor’ is a crucible used to hold or contain the sorbent. In an embodiment of the present invention, the contactor is partially transparent to radio frequency or microwaves. In an alternative embodiment of the invention, the contactor contains specific covalently bound groups to allow absorption of specific radio frequency or microwaves. In an embodiment of the present invention, the contactor is fabricated from polytetrafluoroethylene (PTFE), polymers with low dielectric constants, alumina based ceramics, corundum, titanium based ceramics, zeolites, fused quartz or a ferrite to minimize absorption in the resonant cavity frequency. In an embodiment of the present invention, the contactor is fabricated from a porous ceramic. In an embodiment of the present invention, the porous ceramic is a silicate, an aluminosilicate, a diatomite, carbon, corundum, silicon carbide or cordierite. In an alternative embodiment of the present invention, the contactor can be cellulose acetate. In an alternative embodiment of the present invention, the contactor can be mesoporous silica. In an alternative embodiment of the present invention, the contactor is fabricated from a glass coated ferromagnetic. In an alternative embodiment of the present invention, the contactor is fabricated from MnFe2O. In an alternative embodiment of the present invention, the contactor is PTFE impregnated with non aqueous hydroxyl group containing molecules. In another alternative embodiment of the present invention, the contactor is PTFE derivatized with hydroxyl groups.
A resonant cavity means a vessel suitable for carbon dioxide radio frequency and/or microwave desorption.
A sorbent is a material that is capable of forming a bond with carbon dioxide molecules present in air. The carbon dioxide molecules in a feed material that is to be processed are absorbed or adsorbed by the sorbent. In an embodiment of the invention, the feed material is atmosphere. In an embodiment of the present invention, the sorbent is a poly amine sorbent. In an embodiment of the present invention, the sorbent is a plastic impregnated with an amine. In an embodiment of the present invention, the sorbent is selected from the group consisting of linear PEI, branched PEI, linear PEI functionalized cellulose acetate silica dioxide, branched PEI functionalized cellulose acetate silica dioxide, PAA poly(allylamine) and PPI poly(propylenimine).
A gas sealable entrance means an opening that separates the outside (e.g., of a resonant cavity) from the inside, through which materials such as contactors can pass from one side to the other (e.g., when loading a resonant cavity with a contactor) which when sealed limits a plurality of gas molecules passing from one the inside to the outside. In an embodiment of the invention, a gas sealable entrance of a resonant cavity with an attached vacuum pump is able to maintain a vacuum differential pressure between the outside and inside of the gas sealable entrance of approximately 0.2 bar. In this range approximately means plus or minus thirty (30) percent.
A cavity is tuned to provide uniform heating means heating through design of the geometrical dimensions of the processing cavity and may include the active manipulation of the electromagnetic standing waves through a variety of methods such as movement of a dielectric material through the cavity, stirring or moving a microwave absorptive material through the cavity.
Deployed means attached, affixed, adhered, inserted, or otherwise associated. A reservoir is a vessel used to contain one or more of a liquid, a gaseous or a solid sample.
In the following description, various aspects of the present invention will be described. However, it will be apparent to those skilled in the art that the present invention may be practiced with only some or all aspects of the present invention. For purposes of explanation, specific numbers, materials, and configurations are set forth in order to provide a thorough understanding of the present invention. However, it will be apparent to one skilled in the art that the present invention may be practiced without the specific details. In other instances, well-known features are omitted or simplified in order not to obscure the present invention.
Carbon-dioxide and CO2 are used herein interchangeably.
Direct Air Capture (DAC) involves the removal and concentration of carbon dioxide from air and is regarded as an attractive and scalable carbon mitigation pathway strategy if carbon dioxide is geologically sequestered or up-converted into materials such as concrete, polymers and carbon fibers. DAC has the potential to achieving net negative emissions at the multi GT/y scale by the year 2050. However, the technologies, costs and process steps involved with DAC can limit its application to larger-scale embodiments that are not well-suited for market adoption requiring compression, liquefaction, storage and transportation of the carbon dioxide to the commercial customer. On-site production of carbon dioxide from DAC to existing industries that use carbon dioxide can decrease the costs of carbon dioxide to the customers and provide a more sustainable supply while meeting emission reduction targets/requirements.
DAC requires the contact of carbon dioxide from the air onto a sorbent followed by desorption of the carbon dioxide to collect the gas. There are two predominant methods for carbon dioxide capture currently in the state of commercialization or pre-commercialization—alkali aqueous solutions and amines. For each method, there is a preferred carbon dioxide release or extraction system. ‘Steam stripping’ systems supply the energy required to break an amine-carbon dioxide chemical bond when amines are used to capture the carbon dioxide.
Amine systems are generally described in two categories: liquid amine contactors and solid amine contactors (including amine-tethered MOFs). However, amines can be degraded under oxidizing conditions and at elevated temperatures or in the presence of humidity or steam. Alkali liquid systems contact carbon dioxide from air to an aqueous alkaline solution to form carbonates which are then decomposed using heat to produce carbon dioxide requiring large capital and energy costs and do not lend themselves to applications that fit the merchant carbon dioxide market without transportation.
DAC requires the contact of carbon dioxide from the air onto a sorbent followed by desorption of the carbon dioxide to collect the gas. There are currently two predominant methods for carbon dioxide capture (i) absorption via alkali aqueous solutions and (ii) adsorption via chemisorption of amines or physisorption of zeolites. Alkali aqueous solution systems contact gaseous carbon dioxide (from air) with an aqueous alkaline solution to form carbonates, thereby removing the carbon dioxide from the air. The carbonates are then decomposed using heat to generate the carbon dioxide and regenerate the alkali solution. The process requires large capital costs and high energy costs. The process does not lend itself to applications that fit the merchant carbon dioxide market without transportation. Amine systems are generally described in two categories: liquid amine contactors and solid (polymeric) amine contactors, including amine-tethered Metal Organic Frameworks (MOFs). Solid polymeric amine systems are generally impregnated or grafted onto porous support structures such as silica, clays, zeolites and carbons. Polymeric amine DAC systems require CO2 regeneration via heat (TSA thermal swing adsorption), pressure (VSA vacuum swing adsorption) or a combination (TVSA thermal vacuum swing adsorption).
CO2 is useful to industry and DAC enables utilization of lower-cost and more sustainable supplies of CO2 to existing and future markets. Additionally, CO2 supplied from DAC can replace existing CO2 sources used in industry that ultimately increase atmospheric CO2 loading. DAC can be used meet emission reduction requirements of industry.
The first order considerations when designing DAC systems are a) the energy cost of contacting carbon dioxide with the sorbent, b) regeneration of the sorbent, and c) capital and maintenance cost of the system.
DAC requires moving large mass volumes of air through the sorbent contactor due to the low concentrations of CO2 in air. Therefore, the energy cost of contacting carbon dioxide via the movement of air dictates that low pressure-drop contactors such as laminar flow contactors are much preferred over alternative embodiments, as pressure drop and therefore energy consumption of laminar flow contact has a linear relationship to airspeed velocity, whereas turbulent flow increases with the square of air velocity and is therefore exponentially more costly. In the laminar flow contactor, carbon dioxide is driven towards the amine capture sites primarily via diffusion gradient perpendicular to the airflow, and secondarily due to shear forces present in laminar flow. Further, the pressure drop through the contactor is low enough so as not to contribute significantly to the overall cost of the process. Extruded monolithic contactors such as those used in catalytic converters of automobiles have excellent properties in as much as they maximize surface area per pressure drop enabling high mass transfer of carbon dioxide adsorption in the laminar flow regime.
Due to the fact that DAC requires contacting low concentrations of carbon dioxide from the air at high mass flow rates, higher airspeeds are preferred to maximize the amount of CO2 captured in a given contactor volume. This requires an exponentially higher pressure drop and therefore energy cost. In the laminar flow regime inside the monolithic contactor, carbon dioxide is driven towards the amine capture sites primarily via a diffusion gradient which is perpendicular to the airflow, and secondarily due to shear forces present in laminar flow. Therefore a laminar flow regime contactor maximizes mass transfer while minimizing energy costs associated with active DAC. A laminar flow regime is additionally preferred over turbulent flow as the diffusion force for carbon dioxide capture happens quickly and is a driving force that does not require an additional energy input other than the movement of air in the laminar flow regime.
Desorption represents the largest energy cost for DAC, although an argument can be made that leveraging waste heat reduces desorption costs; however, this approach limits the market potential of DAC by requiring co-location with waste thermal heat sources.
Commercially available monolithic contactors maximize surface area per pressure drop enabling high mass transfer of carbon dioxide adsorption in the laminar flow regime. For DAC, carbon dioxide loading of the contactors is a function of airspeed, amine loading and breakthrough carbon dioxide efficiencies. Alternative laminar flow contactors with sufficient porosity are also suitable.
P=v
air
*A*Pd*1/Efffan Equation 1
Where P is the power (energy) requirement for movement of air through a contactor, v is the air velocity given in m/s, A is the contactor frontal surface area given in m2, Pd is the pressure drop given in Pa (J/m3) and Eff is the fan efficiency.
In an embodiment of the invention, by operating in the laminar flow regime a sorbent can achieve up to 80% carbon dioxide capture.
m
CO2
*
=m
air
*
*C
CO2=ρair*v*A*CCO2 Equation 2
Mass flow rate of carbon dioxide is given by the density of air ρair at STP in kg/m3, v is the velocity of air in m2/s, A is the cross-sectional surface area of the contactor in m2, Cco2 is the concentration of carbon dioxide in air (which is 0.04%).
m
CO2capture
*
=m
CO2
**EffCO2*Dadsorption Equation 3
Where Effco2 is up to 80%, and Dads is 90%. Therefore the mass of carbon dioxide capture is 6.5 kg/hr of carbon dioxide, which at 806 W of power is 124.5 kWh/MT (448 kJ/kg) of carbon dioxide. Given the constraints of fan efficiencies and air concentrations of carbon dioxide, the primary ways to increase the energy efficiency of carbon dioxide capture via laminar flow contactors is to decrease pressure drop (unlikely) or increase the mass transfer of carbon dioxide which would require increasing EFFCO2, Dads or vair.
In an embodiment of the present invention, the poly amine sorbent can be linear polyethylenimine (PEI), branched PEI, aziridine, diethylenetriamine, triethylenetetramine, diethyleanetriamino organosilane, and aminopropyl organosilane. In an alternative embodiment of the present invention, the poly amine sorbent can be linear PEI functionalized cellulose acetate silica dioxide sorbent, branched PEI functionalized cellulose acetate silica dioxide sorbent material, linear PEI incorporated into a metal organic framework, branched PEI incorporated into a metal organic framework, and amine incorporated into a metal organic framework. In another alternative embodiment of the present invention, the poly amine sorbent can be a mesoporous material selected from the group consisting of M41S, FSM-16 and SBA-15 modified with amino groups such as polyethylene MCM-41, or 3-trimethoxysilylpropyl diethylenetriamine SBA-15. In an alternative embodiment of the present invention, alternative higher adsorption capacity sorbents and alternative contactor materials can be used with MWSD. For example, some amine-silica sorbent materials which are known to degrade to some extent in the presence of steam may be useful with the present invention where desorption is under sufficiently anhydrous conditions.
Conventional steam stripping technology employs a desorption mechanism which leverages a combination of vacuum and low-temperature steam to provide a rapid and reasonably efficient mechanism of carbon dioxide desorption while reducing the primary deactivation mechanism of oxidation of the amine at elevated temperatures. The adsorption energy for PEI has been measured to be about 94 kJ/mol, or 2,350 kJ/kg carbon dioxide. However, empirical data from commercially designed systems with multiple monoliths are reported to require about 5,000 kJ/kg carbon dioxide. Cooling of the monolith for cyclical adsorption occurs via the contactor wetted surfaces drying via airflow through dissipation of the contactor thermal mass lost to the environment. As a result, the latent energy of the desorption system thermal mass is difficult to recover, limiting overall system energy efficiency and exergy.
The heat of desorption is given by Equation 4 for traditional isothermal regeneration processes:
Where the regeneration heat Qr (kJ/kg carbon dioxide adsorbed), qw is the sorbent working capacity in wt % (typically between 8-10% for PEI), Cp,s is the specific heat of adsorbent (kJ/kgK) around 1.81, Tde is desorption temperature, Tad is adsorption temperature (typical delta around 60), and Ha is the heat of adsorption (kJ/kg carbon dioxide) around 95, Qv is the vaporization heat of water at STP (2257.6 kJ/kg), FH2O is the moisture uptake from air in the sorbent, the latter two are dependent on relative humidity present during adsorption and hydrophilicity of the sorbent.
The total head of desorption is given by the Equation 5:
Q
total=(1−α)Qr+(1−β)Qc+(1−γ)Qs Equation 5
Where Qc is the thermal energy required for the latent heat of the contactor (Cp,c*dT) and Qs is the energy required for the remaining wetted system components. Thermal recovery is considered in the full system design wherein Qr>Qs>Qc; however, the heat recovery efficiency of Qs>>Qr & Qc due to evaporative cooling of the contactor and polymer.
The second law efficiency of the desorption step given by Ha/Qr, and total second law efficiency is given by (Ha+RT ln(P/Po) where P is the final pressure of pure carbon dioxide, Po is the initial partial pressure, R is the ideal gas constant and T is the working temperature.
Typical sorbent loading on the contactor is approximately 30-40 wt %. In this range approximately means plus or minus twenty (20) percent. In conventional VSA and TVSA, system desorption components get larger and require more mass with increased contactor frontal surface area to provide structural stability for the reduced pressure of desorption which increases thermal mass, reducing thermal efficiency with larger contactor frontal surface area and increases overall capital and energy costs.
Radio frequency (RF) irradiation includes radio waves and microwaves (MW). RF irradiation, is the oscillating electromagnetic irradiation in the frequency range of 20 kHz to 1 GHz. Typically, RF below approximately 1 GHz heats via ionic conduction, whereas above 1 GHz, MW heats via dipole heating. In an alternative embodiment of the present invention, RF irradiation at approximately 27.2 MHz, at room temperature will be used to excite the carbamate bond. In another embodiment of the present invention, RF irradiation at approximately 42 MHz at room temperature will be used to excite the carbamate bond. In another alternative embodiment of the present invention, RF irradiation at approximately 915 MHz at room temperature will be used to excite the carbamate bond. In this range approximately means plus or minus twenty percent. In another alternative embodiment of the present invention, the substrate is heated indirectly (without directly exciting the bond) resulting in the excitation of the carbamate bond.
MW irradiation is electromagnetic irradiation in the frequency range of 1 GHz to 300 GHz. In an embodiment of the present invention, MW irradiation at approximately 2.45 GHz at room temperature will be used to excite the carbamate bond. In this range approximately means plus or minus twenty percent. Domestic ‘kitchen’ MW ovens and the majority of dedicated MW reactors for chemical synthesis operate at a frequency of 2.45 GHz (which corresponds to a wavelength of 12.24 cm) to avoid interference with telecommunication and cellular phone frequencies. The energy of the MW photon in this frequency region (0.0016 eV) which is generally too low to break chemical bonds and is also lower than the energy of Brownian motion. Accordingly, microwave irradiation at 2.45 GHz frequency requires additional energy in order to induce chemical reactions. Typically, RF below approximately 1 GHz heats via ionic conduction, whereas above 1 GHz, MW heats via dipole heating coupling to the RF field.
MW heating occurs via direct molecular interactions with the MW radiation affording instantaneous and volumetric heating without the heat transfer restrictions and heat losses associated with conventional conductive or convective heating modes. Microwaves interact directly with the molecules of a reaction mixture transferring energy more rapidly and efficiently than convection techniques that rely on thermal conductivity where heat is transferred to the entire reactor assembly until the target desorption temperature is reached. Microwaves interact with molecules through two methods: dipole rotation and iconic conduction.
Microwave-enhanced chemistry is based on the efficient heating of materials by ‘microwave dielectric heating’ effects. This phenomenon is dependent on the ability of a specific material (solvent or reagent) to absorb MW energy and convert it into heat. The electric component of an electromagnetic field causes heating by two main mechanisms: dipolar polarization and ionic conduction. Irradiation of the sample at MW frequencies results in the dipoles or ions aligning in the applied electric field. As the applied field oscillates, the dipole or ion field attempts to realign itself with the alternating electric field and, in the process, energy is lost in the form of heat through molecular friction and dielectric loss. The amount of heat generated by this process is directly related to the ability of the matrix to align itself with the frequency of the applied field. If the dipole does not have enough time to realign, or reorients too quickly with the applied field, no heating occurs. The allocated frequency of 2.45 GHz used in all commercial systems lies between these two extremes and gives the molecular dipole time to align in the field, but not to follow the alternating field precisely.
In an embodiment of the present invention, a MW swing technology utilizes laminar-flow contactors with solid-amine sorbents coupled with the MWSD step. In an embodiment of the present invention, a continuous mechanism for moving the contactors through the MW desorption cavity can be employed. In an alternative embodiment of the present invention, a process for moving the resonant cavity and waveguide around the sorbent material can be employed.
The presence of moisture or any atmospheric hydration of the amine will resonate with MW energy thereby adding additional thermal energy to the sorbent-CO2 bond.
In practice MW heating generates standing waves based on the dimensions of the resonant cavity and frequency that are correlated with hot/high power spots, and cool/low power spots. In an embodiment of the present invention, by generating uniform heating/power distribution throughout the system near complete desorption of the carbon dioxide can be assured. As the carbamate bonds resonate within the field, the loss factor (tan δ) will change until carbon dioxide desorption occurs, affecting the wave pattern.
In an embodiment of the present invention, the MW irradiation energy can be monitored to optimize the time taken for efficient regeneration of the sorbent and thereby increase productivity and efficiency of the carbon dioxide removal process. In an embodiment of the invention, a microwave generator can be coupled to a specifically designed resonant cavity for carbon dioxide desorption with a Class A/B amplifier which will operate as an oscillator when receiving feedback from the cavity to excite molecular oscillations in the sorbent. In an embodiment of the present invention, a fan field stirrer (wave stirrer or mechanical stirrer) will be used to modify the molecular oscillations in the carbon dioxide bound sorbent generated by the MW irradiation, which affects the standing wave patterns. In an embodiment of the present invention, a wave reflector will be used to modify the molecular oscillations in the carbon dioxide bound sorbent generated by the MW irradiation. In an alternative embodiment of the present invention, the microwave generator is adapted to allow scanning between variable frequencies to optimize the desorption process. In another alternative embodiment of the present invention, the microwave generator is adapted to allow pulse width modulation. In an embodiment of the present invention, the microwave generator can be used to ensure even heating in the desorption cavity allowing for rapid and complete carbon dioxide desorption with higher adsorption duty cycles and faster cooling, when compared to conventional heating. When presented with a mixture of different dielectrics, the microwaves will selectively couple to the higher dielectric loss component. In an embodiment of the invention, the system can be configured to self-frequency modulate enabling the device to automatically search out frequencies that maximize carbon dioxide desorption and direct the MW energy specifically into the desorption bond. In an unexpected result, MWSD can specifically target the enthalpy of desorption without heating a significant amount of contactor thermal mass in addition to the minimum energy required for desorption.
As the applied field oscillates, the dipole or ion field attempts to realign itself with the alternating electric field and, in the process, energy is lost in the form of heat through molecular friction and dielectric loss. The amount of heat generated by this process is directly related to the ability of the matrix to align itself with the frequency of the applied field. If the dipole does not have enough time to realign, or reorients too quickly with the applied field, no heating occurs. The allocated frequency of 2.45 GHz used in most commercial systems lies between these two extremes and gives the molecular dipole time to align in the field, but not to follow the alternating field precisely.
The heating characteristics of a particular material (for example, a solvent) under MW irradiation conditions are dependent on its dielectric properties. The ability of a specific substance to convert electromagnetic energy into heat at a given frequency and temperature is determined by the so-called loss factor tan δ. This loss factor is expressed as the quotient tan δ=ε″/ε′, where ε″ is the dielectric loss, which is indicative of the efficiency with which electromagnetic radiation is converted into heat, and ε′ is the dielectric constant describing the ability of molecules to be polarized by the electric field. A reaction medium with a high tan δ value is required for efficient absorption and, consequently, for rapid heating.
In an embodiment of the present invention, Maximum Power Point Tracking (MPPT) can be used to optimize the structural arrangement of components between the MW source, the location of the contactors, the position of the sorbent and on the contactors, and the power density of the microwaves and the geometry of the microwaves. There are two components to the MPPT, instrumental feedback and software control which result in the ability to change the microwave power density and/or the geometry of the microwaves to provide more efficient heating of the sorbent. In an embodiment of the present invention, MPPT feedback between some sensor inside the device that can determine either a) how much energy is being absorbed by the sorbent, or b) that the EM field provides for even heating throughout the sorbent apparatus. In an embodiment of the present invention, MPPT feedback can be used to ensure desorption of the bonded carbon dioxide between a lower limit of approximately forty (40) percent and an upper limit of approximately ninety (90) percent and to optimize the experimental conditions of the desorption process. In this range approximately means plus or minus twenty (20) percent.
The Dominant DAC Cost is Associated with the Sensible Heat Requirements of the Monolith Contactor
Commercially available extruded parallel channel monolith contactors impregnated with solid-amine sorbents have been shown to be a preferred embodiment for carbon dioxide adsorption from air due to their commercial availability, low pressure drop, high carbon dioxide capacity and cyclical stability. Key elements in designing a practical and commercial DAC process are (i) sorption capacity, (ii) sorption kinetics, (iii) low pressure drop, (iv) practical sorbent regeneration and (v) long sorbent lifetimes
PEI is the current preferred amine because has been found to be highly stable and maintains sufficient carbon dioxide adsorption capacity in the presence of repeated steam cycles up to 120° C. However, the most commonly used amine-silica sorbent materials are known to degrade to some extent in the presence of steam. PEI is a widely commercially available material that can be manufactured at large scales and is available in a number of configurations with different chemical-physical properties, and can be manufactured using different methods including MW heating. Significant work has been done showing that parallel channel low pressure drop monoliths with high mesopore volumes and fully sorbing walls versus wash coats have been shown to be preferred. Many other sorbents with higher amine loading or carbon dioxide binding efficiencies have been tested with varying results to stability through repeated cycling at higher temperatures which does not lend itself to utilizing waste heat.
Several studies and empirical process data have shown that the dominant contribution in cost to adsorption-based DAC is associated with the sensible heat requirements of the monolith and the adsorbent, ranging from 50-70%, which are not easily recoverable in steam-regeneration monolithic processes.
Commercially-available corderite material has been shown to contribute significantly (25-45%) to the overall cost of the process largely due to its high specific heat capacity. The utilization of other mesoporous materials with lower specific heat capacities such as gamma-alumina has been the subject of significant development due to its Cp being approximately half of that for corderite (0.8 vs. 1.4 Jg−1K−1).
Significant work has been done on utilizing alternative materials such as gamma-alumina for the mesoporous contactor, MOFs, polymer hollow fiber sorbents and others.
In an embodiment of the invention, DAC embodiment utilizes low-cost low-pressure drop mesoporous contactors with commercially-available and stable amines and utilizes a desorption process that maximizes second law efficiencies and adsorption duty cycle. The proposed technology utilizes the preferred commercially available laminar-flow contactors (corderite and extruded mesoporous γ-alumina parallel-channel monoliths) with commercially-available solid-amine sorbents coupled with a microwave-assisted desorption step. Due to the nature of the amine-carbon dioxide carbamate bond, the resultant carbamate exhibits a dipole and ionic charge which are directly excitable via electromagnetic fields present in MW radiation. Additionally, the contactor monoliths and carbon dioxide lean sorbents do not have strong dipole moments compared to the carbamate or sorbent-CO2 bond, and are therefore largely transparent to microwaves. Once the sorbent captures carbon dioxide, the resulting carbamate bond exhibits a dipole which resonates in the presence of the MW frequency electromagnetic field until the carbon dioxide is released. Once released, the sorbent has a significantly reduced dipole and a significantly reduced capacity to absorb energy. Therefore, a system can be designed such that the energy used during the desorption step can be used mainly for desorption, maximizing the second law efficiency of desorption and reducing the primary amine deactivation pathway of oxidation at higher temperatures.
In an embodiment of the invention, the key design requirements are: (i) sufficient mass transfer of carbon dioxide adsorption coupled with efficient desorption energy consumption and cycle times; (ii) laminar-flow regime to maximize mass transfer while minimizing energy costs associated with adsorption; and (iii) carbon dioxide adsorption via diffusion in a high mass air flow. The commercially-available monolithic contactors maximize surface area per pressure drop enabling high mass transfer of carbon dioxide adsorption in the laminar flow regime. The technology employs a desorption mechanism which leverages a combination of vacuum and low-temperature steam which together provide a mechanism of carbon dioxide desorption while reducing the primary deactivation mechanism of amine oxidation at regeneration temperatures.
In an embodiment of the invention, water can be added to the contactor prior to microwave desorption
Embodiments contemplated herein include Embodiments P1-P69 following.
Embodiment P1. A Direct Air Capture (DAC) device including a contactor, a polyamine sorbent associated with the contactor, where a plurality of carbon dioxide molecules in the air contacting the polyamine sorbent form a bond with the polyamine sorbent, a vacuum pump, and a resonant cavity including a gas sealable entrance adapted to allow the contactor to enter the resonant cavity and seal the resonant cavity, a vacuum port, where the vacuum pump is in gaseous connection with the vacuum port to evacuate the resonant cavity; and a microwave generator adapted to be electromagnetically connected to the resonant cavity, where the microwave generator is adapted to select a microwave frequency to optimize breaking the bond between the polyamine sorbent and the plurality of carbon dioxide molecules releasing the plurality of carbon dioxide molecules into the vacuum port, where the plurality of gaseous carbon dioxide molecules released by the microwave generator are removed from the resonant cavity through the vacuum port.
Embodiment P2. The DAC device of Embodiment P1, wherein the microwave frequency selected at room temperature is between a lower limit of approximately 0.95 GHz, and an upper limit of approximately 2.5 GHz.
Embodiment P3. The DAC device of Embodiment P1, wherein the microwave generator is adapted to optimize irradiation at frequencies between a lower limit of approximately 1 GHz, and an upper limit of approximately 3 GHz.
Embodiment P4. The DAC device of Embodiment P1, wherein the microwave generator further comprises a variable scanning microwave frequency with a lock in amplifier to affect desorption of the bonded carbon dioxide molecules between a lower limit of approximately forty (40) percent, and an upper limit of approximately ninety five (95) percent.
Embodiment P5. The DAC device of Embodiment P1, wherein the vacuum pump reduces the pressure in the resonant cavity to between a lower limit of approximately 0.1 bar, and an upper limit of approximately 1 bar, where approximately means plus or minus twenty (2) percent.
Embodiment P6. The DAC device of Embodiment P1, wherein the polyamine sorbent is selected from the group consisting of linear polyethylenimine (PEI), branched PEI, aziridine, diethylenetriamine, triethylenetetramine, diethyleanetriamino organosilane, aminopropyl organosilane, linear PEI functionalized cellulose acetate silica dioxide sorbent, branched PEI functionalized cellulose acetate silica dioxide sorbent material, linear PEI incorporated into a metal organic framework, branched PEI incorporated into a metal organic framework, amine incorporated into a metal organic framework, polyethylene MCM-41, and 3-trimethoxysilylpropyl diethylenetriamine SBA-15.
Embodiment P7. A method of capturing carbon dioxide molecules from air with contained release of carbon dioxide molecules including (A) exposing a contactor in which a polyamine sorbent is associated with the contactor to a flow of air, where a plurality of carbon dioxide molecules form a bond with the polyamine sorbent, (B) introducing the contactor into a resonant cavity including (a) a gas sealable entrance adapted to seal the resonant cavity with the contactor inside the resonant cavity, (b) a vacuum port in gaseous connection with a vacuum pump, and (c) a microwave generator adapted to be electromagnetically connected to the resonant cavity, where the microwave generator is adapted to select a microwave frequency to optimize breaking the bond with the polyamine sorbent, (C) sealing the resonant cavity, (D) evacuating the sealed resonant cavity, (E) irradiating the polyamine sorbent with the selected microwave frequency to release the plurality of carbon dioxide molecules into the resonant cavity, and (F) removing the plurality of carbon dioxide molecules in the resonant cavity through the vacuum port using the vacuum pump.
Embodiment P8. The method of Embodiment P7, wherein the moisture content of the evacuated resonant cavity in step (D) is between a lower limit of approximately 10 μg Limit of Detection (LOD), and an upper limit of approximately 10 mg LOD.
Embodiment P9. The method of Embodiment P7, wherein the flow of air is between a lower limit of approximately 0.5 m2/s, and an upper limit of approximately 5 m2/s.
Embodiment P10. A continuous DAC device including a moving stage, a plurality of contactors located on the moving stage, a polyamine sorbent associated with each of the plurality of contactors, an outlet, where the outlet is adapted to allow a laminar flow of air to pass over the polyamine sorbent associated with each of the plurality of contactors, where a plurality of carbon dioxide molecules in the air form a bond with the polyamine sorbent, a vacuum pump, and a resonant cavity including one or both a sealable entrance and a sealable exit adapted to allow one or more of the plurality of contactors to enter the resonant cavity and seal the resonant cavity containing the one or more of the plurality of contactors, a vacuum port in gaseous connection with the vacuum pump adapted to evacuate the sealed resonant cavity, and a microwave generator adapted to be electromagnetically connected to the resonant cavity, where the microwave generator is adapted to select a microwave frequency to optimize breaking the bond between the polyamine sorbent and the plurality of carbon dioxide molecules releasing the plurality of carbon dioxide molecules into the vacuum port, where the plurality of gaseous carbon dioxide molecules released by the microwave generator are removed from the resonant cavity through the vacuum port.
Embodiment P11. The DAC device of Embodiment P10, wherein the microwave generator is adapted to vary the microwave frequency to optimize the desorption of the plurality of carbon dioxide molecules.
Embodiment P12. The DAC device of Embodiment P10, wherein the microwave generator is adapted to allow pulse width modulation to optimize the desorption of the plurality of carbon dioxide molecules.
Embodiment P13. The DAC device of Embodiment P10, wherein the microwave frequency is between a lower limit of approximately 0.9 GHz, and an upper limit of approximately 2.5 GHz.
Embodiment P14. The DAC device of Embodiment P10, wherein the microwave generator is adapted to optimize irradiation at frequencies between a lower limit of approximately 0.9 GHz, and an upper limit of approximately 300 GHz.
Embodiment P15. The DAC device of Embodiment P10, wherein the microwave generator further comprises a variable scanning microwave frequency with a lock in amplifier to ensure desorption of the carbon dioxide molecules between a lower limit of approximately forty (40) percent, and an upper limit of approximately ninety five (95) percent.
Embodiment P16. The DAC device of Embodiment P10, wherein the vacuum pump reduces the pressure in the resonant cavity to between a lower limit of approximately 1 mbar, and an upper limit of approximately 50 mbar.
Embodiment P17. The DAC device of Embodiment P10, wherein the polyamine sorbent is selected from the group consisting of polyamine sorbent is selected from the group consisting of linear polyethylenimine (PEI), branched PEI, aziridine, diethylenetriamine, triethylenetetramine, diethyleanetriamino organosilane, aminopropyl organosilane, linear PEI functionalized cellulose acetate silica dioxide sorbent, branched PEI functionalized cellulose acetate silica dioxide sorbent material, linear PEI incorporated into a metal organic framework, branched PEI incorporated into a metal organic framework, amine incorporated into a metal organic framework, polyethylene MCM-41, and 3-trimethoxysilylpropyl diethylenetriamine SBA-15.
Embodiment P18. A method of continuous capture of carbon dioxide molecules from air with contained release of carbon dioxide molecules including (A) exposing a plurality of contactors in which a polyamine sorbent is associated with each of the plurality of contactors to a laminar flow of air, where a plurality of carbon dioxide molecules form a bond with the polyamine sorbent, (B) introducing one or more of the plurality of contactors into a resonant cavity including (a) one or both a gas sealable entrance and a gas sealable exit adapted to allow one or more of the plurality of contactors to (i) enter the resonant cavity, (ii) seal the resonant cavity with the one or more of the plurality of contactors inside the resonant cavity, and (iii) exit the resonant cavity, (b) a vacuum port in gaseous connection with a vacuum pump, and (c) a microwave generator adapted to be electromagnetically connected to the resonant cavity, where the microwave generator is adapted to select a microwave frequency to optimize breaking the bond with the polyamine sorbent, (C) sealing the resonant cavity, (D) evacuating the sealed resonant cavity, (E) irradiating the polyamine sorbent with the selected microwave frequency to release the plurality of carbon dioxide molecules into the resonant cavity, (F) removing the plurality of carbon dioxide molecules in the resonant cavity through the vacuum port using the vacuum pump, (G) removing the one or more of the plurality of contactors from the resonant cavity, and (H) repeating steps (B) through (G) to continuously capture carbon dioxide molecules from air with contained release of carbon dioxide molecules.
Embodiment P19. The method of Embodiment P18, further comprising introducing humidity in one or both step (A) and step (E).
Embodiment P20. A DAC device including a contactor, a polyamine sorbent associated with the contactor, where a plurality of carbon dioxide molecules in the air contacting the polyamine sorbent form a bond with the polyamine sorbent, a vacuum pump, and a resonant cavity including a gas sealable entrance adapted to allow the contactor to enter the resonant cavity and seal the resonant cavity, a vacuum port, where the vacuum pump is in gaseous connection with the vacuum port to evacuate the resonant cavity, and a radio frequency generator adapted to be electromagnetically connected to the resonant cavity, where the microwave generator is adapted to select a radio frequency to optimize breaking the bond between the polyamine sorbent and the plurality of carbon dioxide molecules releasing the plurality of carbon dioxide molecules into the vacuum port, where the plurality of gaseous carbon dioxide molecules released by the radio frequency generator are removed from the resonant cavity through the vacuum port.
Embodiment P21. The DAC device of Embodiment P20, wherein the radio frequency is between a lower limit of approximately 12 MHz, and an upper limit of approximately 14 MHz.
Embodiment P22. The DAC device of Embodiment P20, wherein the radio frequency is between a lower limit of approximately 27 MHz, and an upper limit of approximately 42 MHz.
Embodiment P23. The DAC device of Embodiment P20, wherein the radio frequency is between a lower limit of approximately 0.9 GHz, and an upper limit of approximately 1 GHz.
Embodiment P24. The DAC device of Embodiment P20, wherein the radio frequency generator is adapted to optimize irradiation at frequencies between a lower limit of approximately 100 kHz, and an upper limit of approximately 1 GHz.
Embodiment P25. The DAC device of Embodiment P20, wherein the radio frequency generator output power is adjustable between a lower limit of approximately 50 dBm, and an upper limit of approximately 100 dBm.
Embodiment P26. The DAC device of Embodiment P20, wherein the vacuum pump reduces the pressure in the resonant cavity to between a lower limit of approximately 1 mbar, and an upper limit of approximately 50 mbar.
Embodiment P27. The DAC device of Embodiment P20, wherein the polyamine sorbent is selected from the group consisting of polyamine sorbent is selected from the group consisting of linear polyethylenimine (PEI), branched PEI, aziridine, diethylenetriamine, triethylenetetramine, diethyleanetriamino organosilane, aminopropyl organosilane, linear PEI functionalized cellulose acetate silica dioxide sorbent, branched PEI functionalized cellulose acetate silica dioxide sorbent material, linear PEI incorporated into a metal organic framework, branched PEI incorporated into a metal organic framework, amine incorporated into a metal organic framework, polyethylene MCM-41, and 3-trimethoxysilylpropyl diethylenetriamine SBA-15.
Embodiment P28. The DAC device of Embodiment P20, further comprising a mechanical stirrer located within the resonant cavity to stir the electromagnetic field.
Embodiment P29. The DAC device of Embodiment P20, further comprising mounting the contactors on a holder affixed to a moving stage to facilitate movement of the contactors and static components located within the resonant cavity that do not move in relation to the motion of the contactors, where the motion of the contactors relative to the static components stir the electromagnetic field.
Embodiment P30. The DAC device of Embodiment P20, further comprising mounting the contactors on a holder affixed to a moving stage to facilitate movement of the contactors and static components located within the resonant cavity that do not move in relation to the motion of the contactors, where the motion of the contactors relative to the static components dissipate heat evenly within the resonant cavity.
Embodiment P31. The DAC device of Embodiment P20, wherein where the contactors are tuned to heat between, where the motion of the contactors relative to the static components stir the electromagnetic field.
Embodiment P32. A method of capturing carbon dioxide molecules from air with contained release of carbon dioxide molecules including (A) exposing a contactor in which a polyamine sorbent is associated with the contactor to a laminar flow of air, where a plurality of carbon dioxide molecules form a bond with the polyamine sorbent, (B) introducing the contactor into a resonant cavity including (a) a gas sealable entrance adapted to allow the resonant cavity to seal with the contactor inside the resonant cavity, (b) a vacuum port in gaseous connection with a vacuum pump, and (c) a radio frequency generator adapted to be electromagnetically connected to the resonant cavity, where the microwave generator is adapted to select a radio frequency to optimize breaking the bond with the polyamine sorbent, (C) sealing the resonant cavity, (D) evacuating the sealed resonant cavity, (E) irradiating the polyamine sorbent with the selected radio frequency to release the plurality of carbon dioxide molecules into the resonant cavity, and (F) removing the plurality of carbon dioxide molecules in the resonant cavity through the vacuum port using the vacuum pump.
Embodiment P33. The method of Embodiment P32, wherein the moisture content of the sealed resonant cavity after evacuation in step (D) is between a lower limit of approximately 10 μg LOD, and an upper limit of approximately 10 mg LOD.
Embodiment P34. A DAC device including a moving stage, a plurality of contactors located on the moving stage, a polyamine sorbent associated with each of the plurality of contactors, an outlet, where the outlet is adapted to allow a laminar flow of air to pass over the polyamine sorbent associated with each of the plurality of contactors, where a plurality of carbon dioxide molecules in the air form a bond with the polyamine sorbent, a vacuum pump, and a resonant cavity including one or both a sealable entrance and a sealable exit, where one or both the sealable entrance and the sealable exit are adapted to allow one or more of the plurality of contactors to enter the resonant cavity and seal the resonant cavity containing the one or more of the plurality of contactors, a vacuum port in gaseous connection with the vacuum pump adapted to evacuate the sealed resonant cavity, and one or more radio frequency generators adapted to be electromagnetically connected to the resonant cavity, where one or more of the one or more microwave generators are adapted to select a radio frequency to optimize breaking the bond between the polyamine sorbent and the plurality of carbon dioxide molecules releasing the plurality of carbon dioxide molecules into the vacuum port, where the plurality of gaseous carbon dioxide molecules released by the one or more radio frequency generators are removed from the resonant cavity through the vacuum port.
Embodiment P35. The DAC device of Embodiment P34, wherein the shape of the resonant cavity is designed based on a specific radio frequency or set of frequencies used by at least one of the one or more radio frequency generator to affect desorption of the plurality of carbon dioxide molecules.
Embodiment P36. The DAC device of Embodiment P34, wherein at least one of the one or more radio frequency generators is adapted to vary the radio frequency to optimize the desorption of the plurality of carbon dioxide molecules.
Embodiment P37. The DAC device of Embodiment P34, wherein a mechanical element inside the Electro Magnetic (EM) field is moved in relationship to a waveguide to affect the distribution of the EM field.
Embodiment P38. The DAC device of Embodiment P34, wherein at least one of the one or more radio frequency generators generates a radio frequency between a lower limit of approximately 12 MHz, and an upper limit of approximately 14 MHz Torr.
Embodiment P39. The DAC device of Embodiment P34, wherein at least one of the one or more radio frequency generators generates a radio frequency between a lower limit of approximately 27 MHz, and an upper limit of approximately 42 MHz Torr.
Embodiment P40. The DAC device of Embodiment P34, wherein at least one of the one or more radio frequency generators generates a radio frequency between a lower limit of approximately 0.9 GHz, and an upper limit of approximately 1 GHz Torr.
Embodiment P41. The DAC device of Embodiment P34, wherein the radio frequency generator is adapted to optimize irradiation at frequencies between a lower limit of approximately 100 kHz, and an upper limit of approximately 1 GHz.
Embodiment P42. The DAC device of Embodiment P34, wherein the vacuum pump reduces the pressure in the resonant cavity to between a lower limit of approximately 0.2 bar, and an upper limit of approximately 0.8 bar.
Embodiment P43. The DAC device of Embodiment P34, wherein the polyamine sorbent is selected from the group consisting of polyamine sorbent is selected from the group consisting of linear polyethylenimine (PEI), branched PEI, aziridine, diethylenetriamine, triethylenetetramine, diethyleanetriamino organosilane, aminopropyl organosilane, linear PEI functionalized cellulose acetate silica dioxide sorbent, branched PEI functionalized cellulose acetate silica dioxide sorbent material, linear PEI incorporated into a metal organic framework, branched PEI incorporated into a metal organic framework, amine incorporated into a metal organic framework, polyethylene MCM-41, and 3-trimethoxysilylpropyl diethylenetriamine SBA-15.
Embodiment P44. The DAC device of Embodiment P34, further comprising a Maximum Power Point Tracking system to optimize the microwave frequency.
Embodiment P45. A method of continuous capture of carbon dioxide molecules from air with contained release of carbon dioxide molecules including (A) exposing a plurality of contactors in which a polyamine sorbent is associated with each of the plurality of contactors to a laminar flow of air, where a plurality of carbon dioxide molecules form a bond with the polyamine sorbent, (B) introducing one or more of the plurality of contactors into a resonant cavity including (a) one or both a gas sealable entrance and a gas sealable exit adapted to allow one or more of the plurality of contactors to (i) enter the resonant cavity, (ii) seal the resonant cavity with the one or more of the plurality of contactors inside the resonant cavity, and (iii) exit the resonant cavity, (b) a vacuum port in gaseous connection with a vacuum pump, and (c) a radio frequency generator adapted to be electromagnetically connected to the resonant cavity, where the microwave generator is adapted to select a radio frequency to optimize breaking the bond with the polyamine sorbent, (C) sealing the resonant cavity, (D) evacuating the sealed resonant cavity, (E) irradiating the polyamine sorbent with the selected radio frequency to release the plurality of carbon dioxide molecules into the resonant cavity, (F) removing the plurality of carbon dioxide molecules in the resonant cavity through the vacuum port using the vacuum pump, (G) removing the one or more of the plurality of contactors from the resonant cavity, and (H) repeating steps (B) through (G) to continuously capture carbon dioxide molecules from air with contained release of carbon dioxide molecules.
Embodiment P46. The method of Embodiment P45, wherein the radio frequency includes pulsed width modulation.
Embodiment P47. The method of Embodiment P45, wherein the radio frequency generator is turned off to modulate the frequency.
Embodiment P48. The method of Embodiment P45, further comprising passing the carbon dioxide captured is passed over one or more compounds selected from the group consisting of molecular sieves, zeolites and activated carbon.
Embodiment P49. The method of Embodiment P45, further comprising using a Maximum Power Point Tracking system to optimize the microwave frequency.
Embodiment P50. The method of Embodiment P45, further comprising tuning the contactor to heat within the 2.4-2.5 GHz band which conducts thermal energy to the polyamine sorbent.
Embodiment P51. An amplifier of a DAC device including a contactor, a polyamine sorbent associated with the contactor, where a plurality of carbon dioxide molecules in the air contacting the polyamine sorbent form a bond with the polyamine sorbent, a vacuum pump, and a resonant cavity including a gas sealable entrance adapted to allow the contactor to enter the resonant cavity and seal the resonant cavity, a vacuum port, where the vacuum pump is in gaseous connection with the vacuum port to evacuate the resonant cavity, and a microwave generator adapted to be electromagnetically connected to the resonant cavity, where the resonant cavity for carbon dioxide desorption with a Class A/B amplifier is designed such that the resonant cavity will operate as an oscillator when receiving feedback from the resonant cavity to excite molecular oscillations in the sorbent.
Embodiment P52. The amplifier of a DAC device of Embodiment P51, further comprising the microwave generator adapted to scan and vary the frequency.
Embodiment P53. The amplifier of a DAC device of Embodiment P51, further comprising the microwave generator adapted to vary pulse width modulation.
Embodiment P54. The amplifier of a DAC device of Embodiment P51, further comprising modulating the frequency.
Embodiment P55. The amplifier of a DAC device of Embodiment P51, wherein the microwave generator is powered solely by a photovoltaic cell.
Embodiment P56. The amplifier of a DAC device of Embodiment P51, wherein the microwave generator is powered solely by a source of wind energy.
Embodiment P57. A method of manufacture of carbon dioxide molecules from a continuous DAC device introducing a laminar flow of air into a resonant cavity comprising an entrance, an exit, a moving stage, a contactor and a polyamine sorbent associated with the contactor, where a plurality of carbon dioxide molecules present in the air covalently bond with the polyamine sorbent, and irradiating the polyamine sorbent with microwave frequency generated by a microwave generator, where the microwave generator is adapted to select a microwave frequency to optimize breaking the bond between the polyamine sorbent and the plurality of carbon dioxide molecules releasing the carbon dioxide molecules.
Embodiment P58. The method of Embodiment P7, wherein the flow of air is laminar.
Embodiment P59. A continuous DAC device including a contactor, a polyamine sorbent associated with the contactor, an outlet, where the outlet is adapted to allow a flow of air to pass over the polyamine sorbent associated with the contactor, where a plurality of carbon dioxide molecules in the air form a bond with the polyamine sorbent, and a resonant cavity including one or both a sealable entrance and a sealable exit adapted to move to allow the contactor to be in contact with a microwave generator adapted to electromagnetically contact the resonant cavity, where the microwave generator is adapted to select a microwave frequency to optimize breaking the bond between the polyamine sorbent and the plurality of carbon dioxide molecules releasing the plurality of carbon dioxide molecules, where the plurality of gaseous carbon dioxide molecules released by the microwave generator are removed from the resonant cavity.
Embodiment P60. The DAC device of Embodiment P59, wherein the microwave generator is adapted to vary the microwave frequency to optimize the desorption of the plurality of carbon dioxide molecules.
Embodiment P61. The DAC device of Embodiment P59, wherein the microwave generator is adapted to allow pulse width modulation to optimize the desorption of the plurality of carbon dioxide molecules.
Embodiment P62. The DAC device of Embodiment P59, wherein the microwave frequency is between a lower limit of approximately 0.9 GHz, and an upper limit of approximately 2.5 GHz.
Embodiment P63. The DAC device of Embodiment P59, wherein the microwave generator is adapted to optimize irradiation at frequencies between a lower limit of approximately 0.9 GHz, and an upper limit of approximately 3 GHz.
Embodiment P64. The DAC device of Embodiment P59, wherein the microwave generator further comprises a variable scanning microwave frequency with a lock in amplifier to ensure desorption of the carbon dioxide molecules between a lower limit of approximately forty (40) percent, and an upper limit of approximately ninety five (95) percent.
Embodiment P65. The DAC device of Embodiment P59, wherein the vacuum pump reduces the pressure in the resonant cavity to between a lower limit of approximately 1 mbar, and an upper limit of approximately 50 mbar.
Embodiment P66. The DAC device of Embodiment P59, wherein the polyamine sorbent is selected from the group consisting of polyamine sorbent is selected from the group consisting of linear polyethylenimine (PEI), branched PEI, aziridine, diethylenetriamine, triethylenetetramine, diethyleanetriamino organosilane, aminopropyl organosilane, linear PEI functionalized cellulose acetate silica dioxide sorbent, branched PEI functionalized cellulose acetate silica dioxide sorbent material, linear PEI incorporated into a metal organic framework, branched PEI incorporated into a metal organic framework, amine incorporated into a metal organic framework, polyethylene MCM-41, and 3-trimethoxysilylpropyl diethylenetriamine SBA-15.
Embodiment P67. The DAC device of Embodiment P58, further comprising a vacuum pump adapted to one or both evacuate the resonant cavity and remove the carbon dioxide released from the polyamine sorbent.
Embodiment P68. The DAC device of Embodiment P67, where the vacuum pump reduces the pressure in the resonant cavity to between a lower limit of approximately 0.2 bar and an upper limit of approximately 1 bar.
Embodiment P69. The method of Embodiment P7, where a moisture content of the resonant cavity is reduced between a lower limit of approximately 10 percent and an upper limit of approximately 80 percent. In this range approximately means plus or minus thirty (30) percent.
While the systems, methods, and devices have been illustrated by describing examples, it is not the intention of the applicants to restrict or in any way limit the scope of the appended claims to such detail. It is, of course, not possible to describe every conceivable combination of components or methodologies for purposes of describing the systems, methods, and devices provided herein. Additional advantages and modifications will readily be apparent to those skilled in the art. Therefore, the invention, in its broader aspects, is not limited to the specific details, the representative system and method or device shown and described. Accordingly, departures may be made from such details without departing from the spirit or scope of the applicant's general inventive concept. Thus, this application is intended to embrace alterations, modifications, and variations that fall within the scope of the appended claims. Furthermore, the preceding description is not meant to limit the scope of the invention. Rather, the scope of the invention is to be determined by the appended claims and their equivalents.
This application is a 371 U.S. national stage of and claims priority to (i) Patent Cooperation Treaty Application PCT/US2021/042834, entitled “APPARATUS, METHOD AND SYSTEM FOR DIRECT AIR CAPTURE UTILIZING ELECTROMAGNETIC EXCITATION RADIATION DESORPTION OF SOLID AMINE SORBENTS TO RELEASE CARBON DIOXIDE”, inventor: Matthew Atwood, filed Jul. 22, 2021, which claims the priority benefit of (ii) U.S. Provisional Application No. 63/055,285 entitled “APPARATUS, METHOD AND SYSTEM FOR DIRECT AIR CAPTURE UTILIZING ELECTROMAGNETIC EXCITATION RADIATION DESORPTION OF SOLID AMINE SORBENTS TO RELEASE CARBON DIOXIDE”, inventor: Matthew Atwood filed Jul. 22, 2020, which applications (i)-(ii) are herein expressly incorporated by reference in their entireties and for all purposes.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/US2021/042834 | 7/22/2021 | WO |
| Number | Date | Country | |
|---|---|---|---|
| 63055285 | Jul 2020 | US |
