摘要:
This invention is directed to a molecular sieve having acid catalyst sites and a method of maintaining the acid catalyst sites of a template-containing silicoaluminophosphate molecular sieve. The method comprises providing a template-containing silicoaluminophosphate molecular sieve and heating the molecular sieve in an oxygen depleted environment under conditions effective to maintain or preserve the number of acid catalyst sites. The heated molecular sieve exhibits at least one peak in the infrared region in a range of from 3630 cm−1 to 3580 cm−1. Preferably, the heated molecular sieve exhibits a combined peak area in the 3630 cm−1 to 3580 cm−1 range of at least 10% of a total peak area of all peaks in an infrared region between 4000 cm−1 to 3400 cm−1.
摘要:
In a method of synthesizing a silicoaluminophosphate molecular sieve having 90+% CHA framework-type character, a reaction mixture is prepared comprising sources of water, silicon, aluminum, and phosphorus, as well as an organic template. In one aspect, the reaction mixture is heated at more than 10° C./hour to a crystallization temperature and is retained at the crystallization temperature or within the crystallization temperature range for a crystallization time from 16 hours to 350 hours to produce the silicoaluminophosphate molecular sieve. In another aspect, the reaction mixture is heated at less than 10° C./hour to a crystallization temperature from about 150° C. to about 225° C. and is then retained there for less than 10 hours to produce the silicoaluminophosphate molecular sieve. The molecular sieve can then be recovered from the reaction mixture and, preferably, used in a hydrocarbon conversion process, such as oxygenates to olefins.
摘要:
A crystalline microporous silicoaluminophosphate (SAPO) molecular sieve is prepared by: (a) providing a reaction mixture having a molar composition within the following ranges: P:Al from 0.75 to 1.25, Si:Al2 from 0.01 to 0.32, H2O:Al2 from 25 to 50, and R:Al2 from 1 to 3, where R designates a structure directing agent (template), and wherein the molar ratios for the aluminum, phosphorus, and silicon sources are calculated based on the oxide forms; (b) heating the mixture to a crystallization temperature of between 150° C. to 250° C. to form the crystalline molecular sieve within the reaction mixture; and (c) following crystallization in step (b), aging the crystalline molecular sieve in an alkaline liquid at a temperature below the crystallization temperature from 0.5 hour for up to 120 hours. Aging can affect both catalyst life and catalyst activity.
摘要:
The invention relates to a molecular sieve catalyst composition, to a method of making or forming the molecular sieve catalyst composition, and to a conversion process using the catalyst composition. In particular, the invention is directed to making a formulated molecular sieve catalyst composition from a slurry of formulation composition of a synthesized molecular sieve that has not been fully dried, a binder and an optional matrix material. In a more preferred embodiment, the weight ratio of the binder to the molecular sieve and/or the solid content of the slurry is controlled to provide an improved attrition resistant catalyst composition, particularly useful in a conversion process for producing olefin(s), preferably ethylene and/or propylene, from a feedstock, preferably an oxygenate containing feedstock.
摘要:
Disclosed is a method of heat treating a molecular sieve. The method comprises providing a template-containing molecular sieve, heating the molecular sieve under conditions effective to remove a portion of the template from the molecular sieve, and cooling the heated molecular sieve to leave an amount of template effective to cover catalytic sites within the molecular sieve. A catalyst composition is also provided which comprises a molecular sieve having a microporous structure and a binder, wherein between 10 and 90 vol % of the microporous structure is occupied by a material, the material comprising a template or a carbonaceous residue of a template, and the catalyst composition exhibits a Davison Index of not greater than 30.
摘要:
This invention is directed to a method of making an olefin product from an oxygenate feedstock and a method of protecting catalytic activity of a silicoaluminophosphate molecular sieve. The methods comprise providing a silicoaluminophosphate molecular sieve having catalytic sites within the molecular sieve; shielding the catalytic sites to protect from loss of catalytic activity; and contacting the protected sieve in its activated state with an oxygenate feedstock under conditions effective to produce an olefin product before undesirable loss of catalytic activity. Undesirable loss in catalytic activity occurs when activated molecular sieve contacting the oxygenate feedstock has a methanol uptake index of at least 0.15.
摘要:
The invention relates to a molecular sieve catalyst composition, to a method of making or forming the molecular sieve catalyst composition, and to a conversion process using the catalyst composition. In particular, the invention is directed to making a formulated molecular sieve catalyst composition from a slurry of formulation composition of a synthesized molecular sieve that has not been fully dried, a binder and an optional matrix material. In a more preferred embodiment, the weight ratio of the binder to the molecular sieve and/or the solid content of the slurry is controlled to provide an improved attrition resistant catalyst composition, particularly useful in a conversion process for producing olefin(s), preferably ethylene and/or propylene, from a feedstock, preferably an oxygenate containing feedstock.
摘要:
Disclosed is a method of heat treating a molecular sieve. The method comprises providing a template-containing molecular sieve, heating the molecular sieve under conditions effective to remove a portion of the template from the molecular sieve, and cooling the heated molecular sieve to leave an amount of template effective to cover catalytic sites within the molecular sieve. A catalyst composition is also provided which comprises a molecular sieve having a microporous structure and a binder, wherein between 10 and 90 vol % of the microporous structure is occupied by a material, the material comprising a template or a carbonaceous residue of a template, and the catalyst composition exhibits a Davison Index of not greater than 30.
摘要:
A method is disclosed of synthesizing a crystalline material comprising a CHA framework type molecular sieve and having a composition involving the molar relationship: (n)X2O3:YO2, wherein X is a trivalent element; Y is a tetravalent element; and n is from 0 to less than 0.01. The method comprises preparing a reaction mixture capable of forming said material, said mixture comprising a source of water, a source of an oxide of a tetravalent element Y and optionally a source of an oxide of a trivalent element X, wherein the reaction mixture is substantially free of fluoride ions added as HF; maintaining the reaction mixture under conditions sufficient to form crystals of the crystalline material; and than recovering the crystalline material. The reaction mixture comprises either a specific directing agent for directing the formation of a CHA framework type molecular sieve and/or a H2O:YO2 molar ratio of greater than 20. In one embodiment, the resultant crystalline material is free of stacking faults and/or any intergrown phase with an AEI framework type molecular sieve.
摘要:
The invention relates to a molecular sieve catalyst composition, to a method of making or forming the molecular sieve catalyst composition, and to a conversion process using the catalyst composition. In particular, the invention is directed to a conversion process for producing olefin(s), preferably ethylene and/or propylene, from a feedstock, preferably an oxygenate containing feedstock in the presence of a molecular sieve having been synthesized in the presence of a flocculant.