摘要:
The present invention discloses mixed matrix membranes (MMMs) comprising ion-exchanged molecular sieves such as UZM-5 zeolite ion-exchanged with Li+ cation (Li-UZM-5) and a continuous polymer matrix and methods for making and using these membranes. These MMMs, comprising ion-exchanged molecular sieves, in the form of symmetric dense films, asymmetric flat sheets, asymmetric hollow fibers, or thin-film composites, have exhibited simultaneously increased selectivity and permeability (or permeance) over polymer-only membranes and the mixed matrix membranes made from molecular sieves that have not been ion exchanged for gas separations. These MMMs are suitable for a variety of liquid, gas, and vapor separations such as desalination of water by reverse osmosis, deep desulfurization of gasoline and diesel fuels, ethanol/water separations, pervaporation dehydration of aqueous/organic mixtures, CO2/CH4, CO2/N2, H2/CH4, O2/N2, olefin/paraffin, iso/normal paraffins separations, and other light gas mixture separations.
摘要:
The present invention discloses microporous UZM-5 zeolite membranes, methods for making the same, and methods of separating gases, vapors, and liquids using the same. The small-pore microporous UZM-5 zeolite membrane is prepared by two different methods, including in-situ crystallization of one or more layers of UZM-5 zeolite crystals on a porous membrane support, and a seeding method by in-situ crystallization of a continuous second layer of UZM-5 zeolite crystals on a seed layer of UZM-5 zeolite crystals supported on a porous membrane support. The membranes in the form of disks, tubes, or hollow fibers have superior thermal and chemical stability, good erosion resistance, high CO2 plasticization resistance, and significantly improved selectivity over polymer membranes for gas, vapor, and liquid separations.
摘要:
The present invention discloses microporous UZM-5 zeolite membranes, methods for making the same, and methods of separating gases, vapors, and liquids using the same. The small-pore microporous UZM-5 zeolite membrane is prepared by two different methods, including in-situ crystallization of one or more layers of UZM-5 zeolite crystals on a porous membrane support, and a seeding method by in-situ crystallization of a continuous second layer of UZM-5 zeolite crystals on a seed layer of UZM-5 zeolite crystals supported on a porous membrane support. The membranes in the form of disks, tubes, or hollow fibers have superior thermal and chemical stability, good erosion resistance, high CO2 plasticization resistance, and significantly improved selectivity over polymer membranes for gas, vapor, and liquid separations.
摘要:
The present invention provides a process for making an integrally skinned asymmetric polybenzoxazole hollow fiber membrane comprising spinning a dope solution via a dry-wet phase inversion technique to form a porous integrally skinned asymmetric o-hydroxy substituted polyimide or an o-hydroxy substituted polyamide hollow fiber membrane comprising microporous inorganic molecular sieve followed by thermal rearrangement at a temperature from about 250° to 500° C. to convert the polyimide or polyamide membrane into a polybenzoxazole membrane. These membranes contain microporous inorganic molecular sieve materials that can have a particle size from about 20 nm to 10 μm.
摘要:
Applicants have synthesized a family of microporous aluminosilicate zeolites and substituted versions thereof which are identified as UZM-8. These new compositions can be prepared using either only one or more organoammonium cations, such as diethyldimethylammonium or ethyltrimethylammonium cations and optionally an alkali and/or an alkaline earth cation as structure directing agents. The UZM-8 compositions are described by an empirical formula of Mmn+Rrp+Al1-xExSiyOz and have a unique x-ray diffraction pattern.
摘要:
An aluminosilicate zeolite and substituted versions designated UZM-15 have been synthesized. These zeolites are prepared using an organoammonium cation as a template in which at least one organic group has at least 2 carbon atoms. An example of such a cation is diethyldimethylammonium cation. The template can optionally comprise other organoammonium cations, alkali metals and alkaline earth metals. These UZM-15 materials can be dealuminated by various processes to provide UZM-15HS compositions. Both the UZM-15 and UZM-15HS compositions are useful as catalysts or catalyst supports in various process such as the conversion of cyclic hydrocarbons to non-cyclic hydrocarbons and olefin oligomerization.
摘要:
A family of crystalline aluminosilicate zeolites designated UZM-8HS and derived from UZM-8 have been synthesized. The aluminum content of the UZM-8HS is lower than that of the starting UZM-8 thus changing its ion exchange capacity and acidity. These UZM-8HS are represented by the empirical formula: M1an+Al(1−x)ExSiy′Oz″ and are prepared by treatments such as acid extraction and AFS treatments.
摘要:
Embodiments of a process for recovery of nano zeolites from an aqueous suspension are provided. The process comprises the steps of applying centrifugal force to the aqueous suspension to separate a supernatant phase from a solid phase that comprises the nano zeolites and residuals. The solid phase is contacted with a solution effective to dissolve or digest the residuals and to agglomerate the nano zeolites forming agglomerated nano zeolites. The solution is filtered to recover the agglomerated nano zeolites.
摘要:
A new family of crystalline aluminosilicate zeolites has been synthesized. These zeolites are represented by the empirical formula. Mmn+Rr+Al(1−x)ExSiyOz where M represents a combination of potassium and sodium exchangeable cations, R is a singly charged organoammonium cation such as the propyltrimethylammonium cation and E is a framework element such as gallium. These zeolites are similar to MWW but are characterized by unique x-ray diffraction patterns and compositions and have catalytic properties for carrying out various hydrocarbon conversion processes.
摘要:
Xylene and ethylbenzene isomerization process is catalyzed by the UZM-35 family of crystalline aluminosilicate zeolitic compositions represented by the empirical formula: Mmn+Rr+Al(1-x)ExSiyOz where M represents a combination of potassium and sodium exchangeable cations, R is a singly charged organoammonium cation such as the dimethyldipropylammonium cation and E is a framework element such as gallium. These UZM-35 zeolitic compositions are active and selective in the isomerization of xylenes and ethylbenzene.