摘要:
A catalyst for converting methanol to light olefins and the process for making and using the catalyst are disclosed and claimed. SAPO-34 is a specific catalyst that benefits from its preparation in accordance with this invention. A seed material is used in making the catalyst that has a higher content of the EL metal than is found in the principal part of the catalyst. The molecular sieve has predominantly a roughly rectangular parallelepiped morphology crystal structure with a lower fault density and a better selectivity for light olefins.
摘要:
The present invention discloses method for making defect-free high performance mixed matrix membranes (MMMs) containing a continuous polymer matrix and dispersed molecular sieves such as AlPO-14 or UZM-5. These MMMs can be used for separations. The novel method for making defect-free high performance MMMs comprises: post treating the MMM at a temperature ≧150° C. This new method results in a MMM with either no macrovoids or voids of less than 5 angstroms at the interface of the continuous polymer matrix and the molecular sieves. The MMMs are in the form of symmetric dense film, thin-film composite (TFC), asymmetric flat sheet or asymmetric hollow fiber. These MMMs have good flexibility and high mechanical strength, and exhibit high carbon dioxide/methane (CO2/CH4) selectivity and high CO2 permeance for CO2/CH4 separation. The MMMs are suitable for a variety of liquid, gas, and vapor separations.
摘要:
The present invention discloses methods of separating gases using high performance UV cross-linked polymer functionalized molecular sieve/polymer mixed matrix membranes (MMMs) with either no macrovoids or voids of less than several angstroms at the interface of the polymer matrix and the molecular sieves. These UV cross-linked MMMs were prepared by incorporating polyethersulfone (PES) functionalized molecular sieves such as AIPO-14 and UZM-25 small pore microporous molecular sieves into a continuous UV cross-linkable polyimide polymer matrix followed by UV cross-linking. The UV cross-linked MMMs in the form of symmetric dense film, asymmetric flat sheet membrane, or asymmetric hollow fiber membranes have good flexibility, high mechanical strength, and exhibit significantly enhanced selectivity and permeability over polymer membranes made from corresponding continuous polyimide polymer matrices for carbon dioxide/methane and hydrogen/methane separations. The MMMs of the present invention are suitable for a variety of liquid, gas, and vapor separations.
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:
Methods have been found to prepare fused silica capillary gas chromatographic columns where the stationary phase is a molecular sieve affixed to the silica capillary wall without the aid of an organic binder by modifying the interior surface of the silica prior to contact with the molecular sieve. These totally inorganic columns greatly expand the application and range of gas chromatographic separations and allow the use of non-traditional carrier gases, even air, while not degrading the separation of components. The columns are films of small molecular sieve particles affixed to a silica surface modified by such treatments as hydrogen peroxide, alumina deposition, or silica deposition followed by fixation at 80.degree.-160.degree. C.
摘要:
Non-zeolitic molecular sieves are prepared by contacting a body of alumina or silica-alumina (optionally containing reactive sources of phosphorus pentoxide and/or other elements desired in the non-zeolitic molecular sieve) with a liquid reaction mixture containing a reactive source of phosphorus pentoxide (and optionally reactive sources of silica and/or other elements desired in the non-zeolitic molecular sieve), and an organic templating agent, thereby causing the body to react with the liquid reaction mixture and to form crystals of the non-zeolitic molecular sieve within the body.
摘要:
Crystalline microporous metal aluminophosphates wherein the metal is at least one of Co, Mg, Mn, Fe and Zn are provided having the -43, and -50 structures.
摘要:
A novel family of crystalline, microporous aluminophosphate compositions is synthesized by hydrothermal crystallization at elevated temperatures of aluminophosphate gels containing a molecular structure-forming template. The family comprises a number of distinct species, each with a unique crystal structure. Calcination removes volatile extraneous matter from the intracrystalline void space and yields microporous crystalline adsorbents with uniform pores, the dimensions of which vary, among the individual species, from about 3A to 10A in diameter. The compositions represent a new class of adsorbents of the molecular sieve type, and also exhibit properties somewhat analogous to zeolitic molecular sieves which render them useful as catalysts or catalyst bases in chemical reactions such as hydrocarbon conversions.
摘要:
This invention involves a composition, a method of making, and an application of high plasticization-resistant chemically cross-linked polymeric membranes such as cross-linked cellulose acetate (CA) membrane. These cross-linked polymeric membranes with covalently interpolymer-chain-connected rigid networks showed no decrease in CO2/CH4 ideal selectivity under 690 kPa (100 psig) pure CO2 pressure and also no CO2 plasticization up to 3447 kPa (500 psig) pure CO2 pressure. By using the method of chemical cross-linking as described in this invention, the separation characteristics of the polymeric membranes can be decisively improved. These new cross-linked polymeric membranes can be used not only for gas separations such as CO2/CH4 and CO2/N2 separations, O2/N2 separation, olefin/paraffin separations (e.g. propylene/propane separation), iso/normal paraffins separations, but also for liquid separations such as pervaporation and desalination.
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.