摘要:
The invention is directed to a method of synthesising silicoaluminophosphate and aluminophosphate molecular sieves using synthesis templates that contain at least one template of general formula R1R2N—R3, wherein R1 and R2 are independently selected from the group consisting of alkyl groups having from 1 to 3 carbon atoms and hydroxyalkyl groups having from 1 to 3 carbon atoms; R3 is selected from the group consisting of 4- to 8-membered cycloalkyl groups, optionally substituted by 1 to 3 alkyl groups having from 1 to 3 carbon atoms, and 4- to 8-membered heterocyclic groups having from 1 to 3 heteroatoms, said heterocyclic groups being optionally substituted by 1 to 3 alkyl groups having from 1 to 3 carbon atoms and the heteroatoms in said heterocyclic groups being selected from the group consisting of O, N, and S. In particular, the present invention relates to the synthesis of silicoaluminophosphate molecular sieves of the CHA framework type having a low silicon to aluminium atomic ratio.
摘要:
The present invention provides a process for improving the catalytic activity of small and medium pore acidic zeolite catalyst which comprises the steps of treating a zeolite with a phosphorus compound to form a phosphorus treated zeolite and combining the phosphorus treated zeolite with AlPO.sub.4. Optionally the phosphorus treated zeolite is calcined. The step of combining the zeolite with AlPO.sub.4 may optionally be followed by steaming the combined catalyst. Examples of useful phosphorus containing compounds useful in treating the zeolite include phosphoric acid, ammonium mono or dihydrogen phosphate, organic phosphites, and organophosphines. Preferably the phosphorus containing compound is an ammonium acid phosphate. An additional alternate embodiment provides a process for increasing the hydrothermal stability of a zeolite catalyst which comprises first treating a zeolite with a phosphorus containing compound then blending with AlPO.sub.4. The catalyst of the invention may be combined with other catalysts or used alone. The invention may be used in a process for cracking hydrocarbons which comprises contacting a hydrocarbon feedstock with a catalyst prepared as described above.
摘要:
A process for producing an aluminosilicate molecular sieve comprises crystallizing a reaction mixture comprising water, a source of silica and seeds of a silicoaluminophosphate and/or an aluminophosphate molecular sieve. The resultant aluminosilicate molecular sieve product can advantageously be substantially free of framework phosphorus.
摘要:
A process for producing a silicoaluminophosphate molecular sieve having the LEV framework-type employs at least one source of triethylmethylammonium, R+, ions; as a templating agent. The resultant silicoaluminophosphate molecular sieve is useful as a catalyst in the conversion of methanol to olefins.
摘要:
A molecular sieve comprises at least one intergrown phase of an AFX framework-type molecular sieve and a CHA framework-type molecular sieve and is conveniently synthesized using a combination of N,N,N′N′-tetramethylhexane-1,6-diamine and N,N-dimethylcyclohexylamine as organic directing agents.
摘要:
A molecular sieve comprises at least one intergrown phase of an AFX framework-type molecular sieve and a CHA framework-type molecular sieve and is conveniently synthesized using a combination of N,N,N′N′-tetramethylhexane-1,6-diamine and N,N-dimethylcyclohexylamine as organic directing agents.
摘要:
A novel small pore (metallo)aluminophosphate molecular sieve is disclosed. The as-synthesized material has an X-ray diffraction pattern including the lines listed in Table 1 and is produced in the presence of fluoride ions and 4-dimethylaminopyridine as structure directing agent. The silicoaluminophosphate material has methanol conversion activity and n-hexane cracking activity.
摘要:
The invention is directed to a method of synthesizing a molecular sieve. In particular, the invention is directed to a method for synthesizing a molecular sieve, especially a silicoaluminophosphate molecular sieve, in the presence of a templating agent and a polymeric base. The invention is also directed to formulating the molecular sieve into a catalyst useful in a process for producing olefin(s), preferably ethylene and/or propylene, from a feedstock, preferably an oxygenate containing feedstock.
摘要:
The synthesis of a crystalline aluminophosphate or silicoaluminophosphate molecular sieve having a chabazite-type framework type is conducted in the presence of an organic directing agent having the formula (I) [R1R2R3N—R4]+X− (I) wherein R1, R2 and R3 are independently selected from the group consisting of alkyl groups having from 1 to 3 carbon atoms and hydroxyalkyl groups having from 1 to 3 carbon atoms; R4 is selected from the group consisting of 4- to 8-membered cycloalkyl groups, optionally substituted by 1 to 3 alkyl groups having from 1 to 3 carbon atoms; 4- to 8-membered heterocyclic groups having from 1 to 3 heteroatoms, said heterocyclic groups being optionally substituted by 1 to 3 alkyl groups having from 1 to 3 carbon atoms and the heteroatoms in said heterocyclic groups being selected from the group consisting of O, N, and S; and aromatic groups optionally substituted by 1 to 3 alkyl groups, said alkyl groups having from 1 to 3 carbon atoms; and X− is an anion.
摘要:
In a method of synthesizing a silicoaluminophosphate or aluminophosphate molecular sieve comprising a CHA framework-type material, a synthesis mixture is provided comprising a source of aluminum, a source of phosphorus, optionally a source of silicon and at least one organic template of formula (I): [R1R2R3R4N]+ X− (I) wherein each of R1, R2, R3, and R4 is independently an acyclic alkyl group having at least one carbon atom, the total number of carbon atoms in said alkyl groups R1, R2, R3, and R4 is greater than 8 but less than 16, and X− is an anion. The synthesis mixture can then be crystallized to produce the desired molecular sieve.