摘要:
The present invention provides a method for preparing silica containing molecular sieves which may be mixed with an organic polymer to create a mixed matrix membrane. Further, this invention includes a method of making such a mixed matrix membrane and the membrane itself. A process for separating component gases from a mixture using the subject mixed matrix membrane is also described. The method for preparing silica containing molecular sieves comprises super water washing silica containing molecular sieves to produce water washed molecular sieves which are substantially free of surface remnants. Super water washing also ideally lowers the concentration of alkali metals in the molecular sieves. The water washed sieves are sufficiently free of surface remnants such that when the water washed sieves are subjected to a Sieve Wash Conductivity Test, a wash filtrate is produced having a conductivity of less than 110 micro mhos/cm, more preferably less than 80 micro mhos/cm, even more preferably less than 50 micro mhos/cm, and most preferably less than 30 micro mhos/cm. It is believed that super washing the sieves to this degree will enhance, compared to conventional preparation techniques, the ability of the molecular sieves to bond with an organic polymer to form a highly selective and permeable mixed matrix membrane.
摘要:
The present invention provides a method for preparing silica containing molecular sieves which may be mixed with an organic polymer to create a mixed matrix membrane. Further, this invention includes a method of making such a mixed matrix membrane and the membrane itself. A process for separating component gases from a mixture using the subject mixed matrix membrane is also described. The method for preparing silica containing molecular sieves comprises super water washing silica containing molecular sieves to produce water washed molecular sieves which are substantially free of surface remnants. Super water washing also ideally lowers the concentration of alkali metals in the molecular sieves. The water washed sieves are sufficiently free of surface remnants such that when the water washed sieves are subjected to a Sieve Wash Conductivity Test, a wash filtrate is produced having a conductivity of less than 110 micro mhos/cm, more preferably less than 80 micro mhos/cm, even more preferably less than 50 micro mhos/cm, and most preferably less than 30 micro mhos/cm. It is believed that super washing the sieves to this degree will enhance, compared to conventional preparation techniques, the ability of the molecular sieves to bond with an organic polymer to form a highly selective and permeable mixed matrix membrane.
摘要:
A method is disclosed for synthesizing high-silica molecular sieves having the CHA crystal structure using a structure directing agent comprising a cation derived from 1-adamantamine, 3-quinuclidinol or 2-exo-aminonorbornane. The synthesis is conducted in the absence of fluorine.
摘要:
A boron-containing molecular sieve having the CHA crystal structure and comprising (1) silicon oxide and (2) boron oxide or a combination of boron oxide and aluminum oxide, iron oxide, titanium oxide, gallium oxide and mixtures thereof is prepared using a quaternary ammonium cation derived from 1-adamantamine, 3-quinuclidinol or 2-exo-aminonorbornane as structure directing agent. The molecular sieve can be used for gas separation or in catalysts to prepare methylamine or dimethylamine, to convert oxygenates (e.g., methanol) to light olefins, or for the reduction of oxides of nitrogen n a gas stream (e.g., automotive exhaust).
摘要:
A boron-containing molecular sieve having the CHA crystal structure and comprising (1) silicon oxide and (2) boron oxide or a combination of boron oxide and aluminum oxide, iron oxide, titanium oxide, gallium oxide and mixtures thereof is prepared using a quaternary ammonium cation derived from 1-adamantamine, 3-quinuclidinol or 2-exo-aminonorbornane as structure directing agent. The molecular sieve can be used for minimizing cold start emissions from engines.
摘要:
A process for the production of light olefins from a feedstock comprising an oxygenate or mixture of oxygenates, the process comprising reacting the feedstock at effective conditions over a catalyst comprising boron-containing molecular sieve having the CHA crystal structure and comprising (1) silicon oxide and (2) boron oxide or a combination of boron oxide and aluminum oxide, iron oxide, titanium oxide, gallium oxide and mixtures thereof; and wherein the mole ratio of silicon oxide to boron oxide in said boron-containing molecular sieve is between 15 and 125. A method for production of light olefins, comprising selecting the catalyst and reacting a feedstock comprising an oxygenate or mixture of oxygenates, at effective conditions, over the catalyst. Also, a method for production of light olefins, comprising selecting the catalyst, selecting the oxygenate feedstock, and reacting the feedstock at effective conditions over the catalyst.
摘要:
Engine exhaust is treated with a molecular sieve having the CHA crystal structure and having a mole ratio of greater than 50 of (1) an oxide selected from silicon oxide, germanium oxide or mixtures thereof to (2) an oxide selected from aluminum oxide, iron oxide, titanium oxide, gallium oxide or mixtures thereof.
摘要:
A method is disclosed for synthesizing high-silica molecular sieves having the CHA crystal structure using a structure directing agent comprising a cation derived from 1-adamantamine, 3-quinuclidinol or 2-exo-aminonorbornane. The synthesis is conducted in the absence of fluorine.