Patent Application
20060260185
Gasoline engines produce pollutants in the form or carbon monoxide (CO), unburned hydrocarbons (HC) and nitrogen oxides (NOx). The advent and development of catalytic converters has provided significant reductions in these pollutants.
However, as noted in U.S. Pat. No. 4,891,050, and others, these converters often lose their initial strong activity. The use of platinum group metal containing fuel borne catalysts is suggested by the above noted U.S. Pat. No. 4,891,050, but not all causes of reduced activity can be addressed by the presence of platinum alone.
Significant development over many years has failed to fully address problems such as the loss of active cites on supported platinum catalysts due possibly to inactivation. Possible causes of inactivation are sulfur, phosphorous, hydrocarbons and/or carbon or partially carbonized hydrocarbons.
There is a present need for a treatment for the catalysts and/or a fuel additive or fuel composition that would moderate, control or prevent such inactivation.
The present invention provides a gasoline fuel additive which meets the needs of the art with regard to the above-noted problems. The fuel additive of the invention will comprise platinum, preferably as platinum COD and cerium, preferably in a form dispersible or soluble in gasoline, e.g., cerium octoate, cerium oleate and/or cerium stearate. Dosage rates for the gasoline will provide from about 0.05 to about 2.0 ppm platinum and from about 1 to about 100 ppm cerium. Ratios of the platinum to cerium preferably being within the range of from 1:5 to 1:100. High concentrations of platinum within this range are preferred, e.g., from 1.0 to 2.0. ppm platinum. High ratios of platinum to cerium are also preferred, e.g., from 1:5 to 1:25.
The preferred fuels for treatment according to the invention are well known to those skilled in the art and usually contain a major portion of a normally-liquid fuel such as hydrocarbonaceous petroleum distillate fuel, e.g., motor gasoline as defined by ASTM Specification D-439-73, and suitable additives. Such fuels can also contain non-hydrocarbonaceous materials such as alcohols, ethers, organo-nitro compounds and the like (e.g., methanol, ethanol, diethyl ether, methyl ethyl ether, nitromethane). These are also within the scope of this invention, as are liquid fuels derived from vegetable or mineral sources such as corn, alfalfa, shale, and coal. Examples of such fuel mixtures are combinations of gasoline and ethanol, (i.e., gasohol) diesel fuel and ether, gasoline and nitromethane, etc. Particularly preferred fuels are gasoline combined with from 1 to 25% of ethanol.
Any of the fuel-soluble platinum group metal compositions, e.g., 1,5-cyclooctadiene platinum diphenyl (platinum COD), described in U.S. Pat. No. 4,891,050 to Bowers, et al., U.S. Pat. No. 5,034,020 to Epperly, et al., and U.S. Pat. No. 5,266,083 to Peter-Hoblyn, et al., can be employed as the platinum source. Other suitable platinum group metal catalyst compositions include commercially-available or easily-synthesized platinum group metal acetylacetonates (acac), platinum group metal dibenzylidene acetonates, and fatty acid soaps of tetramine platinum metal complexes, e.g., tetramine platinum oleate. The platinum group metal is preferred at concentrations of 0.01-2.0 ppm platinum w/v, i.e., weight of platinum group metal in mg per volume of fuel in liters. Preferred levels are toward the lower end of this range, e.g., 0.1-0.5 ppm. Platinum COD is the preferred form of platinum for addition to the fuel.
Dosage rates will be lower for continuous treatment and lower within the above range where the doses are intermittent and intended for immediate effect.
The following example provides a formulation of a fuel additive and indicates the dosage level for use in a gasoline engine having an exhaust system including a catalytic converter. These formulations are representative and not limiting.
This is an all Pt or all Pt+Ce formulation. The additive can also be made to provide 0.85/0.15 ppmw Pt/Rh by using a proportionate amount of concentrate (0.3% Rh from Rh(acac)3 in toluene). The compositions above are designed to provide either 1.0 ppm Pt only or 1.0 ppmw Pt+15 ppm Ce in 20 gallons of gasoline from a single 75 ml dose.
The additive of the invention can be blended with gasoline before, during or after fueling an engine. When used as a treatment to reactivate a catalytic converter but not used as part of the routine fueling of the vehicle, it is preferably applied in several high dosages, e.g., for from 2 to 5 tanks full of gasoline.
The above description is for the purpose of teaching the person of ordinary skill in the art how to practice the present invention, and it is not intended to detail all of those obvious modifications and variations of it which will become apparent to the skilled worker upon reading this description. It is intended, however, that all such obvious modifications and variations be included within the scope of the present invention which is defined by the following claims. The claims cover the indicated components and steps in all arrangements and sequences which are effective to meet the objectives intended for the invention, unless the context specifically indicates the contrary.
This claims priority to pending U.S. Provisional Patent Application Ser. No. 60/676,445, filed Apr. 28, 2005, the disclosure of which is hereby incorporated by reference.
| Number | Date | Country | |
|---|---|---|---|
| 60676445 | Apr 2005 | US |
