NSF Award
9560778
95-60778 McCray This Small Business Innovation Research Phase I project is directed toward the development of highly selective membranes for use in the chemical process industry (CPI). The potential advantages of simple and efficient membrane separation processes are well known. Membranes, however, have not made major inroads into the CPI for three reasons: 1) many CPI feed streams contain components that dissolve or swell current membranes or module materials, 2) many CPI separations occur at temperatures too high for commercial modules to withstand, and 3) many membranes that show high selectivity when tested on pure-component feed streams lose this selectivity when operated on multicomponent feed streams. The proposed membrane is a new type of hybrid polymeric material that can be used to make membrane coatings for a wide range of organic/organic separations in the CPI. These coatings will be applied to unique solvent- and temperature-resistant hollow-fiber supports (developed in previous work) to form thin-film-composite (TFC) membranes. These, in turn, will be used in high-efficiency, solvent-resistant modules that will enable the use of membrane technology in many applications for the first time. During Phase I, the hybrid materials will be developed, tested as flat-sheet membranes, and applied to the most promising material as a coating on a solvent-resistant support in a hollow-fiber module. In Phase II, the use of hybrid coatings for a wide range of separations and conduct parametric and long-range tests of modules will be examined. Research conducted during Phases I and II will provide the foundation for field testing and commercialization of the technology in Phase III. Annual CPI expenditures (largely for separation unit operations) exceed $23 billion, with key separations including the separation of mixtures of organics, such as aromatics from aliphatics and olefins from paraffins. Additionally, separation processes account for more than 40% of the energy consumption in t he CPI. TFC membranes based on the proposed hybrid materials could be applied to a wide range of separations in the CPI, including the separation of aromatics from aliphatics (e.g., benzene from gasoline) and olefins from paraffins (e.g., propane from propylene). Examples of potential separation applications range from the treatment of natural gas at the wellhead through the refining process to the production of finished chemicals.
