Production of Aromatics from Methane
AssigneeExxonMobil Chemical Patents Inc.
InventorsNeeraj Sangar, Teng Xu, Larry L. Iaccino, Mobae Afeworki
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Abstract
A catalyst for the conversion of methane to higher hydrocarbons including aromatic hydrocarbons comprises molybdenum or a compound thereof dispersed on an aluminosilicate zeolite, wherein the amount of aluminum present as aluminum molybdate in the catalyst is less than 2700 ppm by weight.
Claims10
A process for converting methane to higher hydrocarbons including aromatic hydrocarbons, the process comprising contacting a feed comprising methane with a regenerated catalyst in a reaction zone under conditions effective to convert said methane to aromatic hydrocarbons,
- wherein said regenerated catalyst comprises molybdenum or a compound thereof dispersed on an aluminosilicate zeolite, wherein said zeolite is selected from a group consisting of ZSM-5, ZSM-11, ZSM-12, ZSM-22, ZSM-23, ZSM-35, ZSM-57 and MCM-22, wherein the amount of aluminum present as aluminum molybdate in said catalyst is less than 2700 ppm by weight;
- said catalyst characterized by the formation of aluminium molybdate during dehydrocyclization of methane to benzene, wherein the catalyst has been regenerated and prior to regeneration aluminum molybdate was present in the catalyst, and
- wherein said catalyst's exposure during dehydrocyclization and regeneration has been limited to not more than 100 wt ppm molecular oxygen and/or ozone at a temperature not in excess of 650° C. for a cumulative time not greater than 10 hours.
A process for reducing the coke selectivity of a molybdenum-containing aluminosilicate zeolite catalyst, the process comprising:
- (a) providing a catalyst comprising molybdenum or a compound thereof dispersed on an aluminosilicate zeolite, wherein said zeolite is selected from a group consisting of ZSM-5, ZSM-11, ZSM-12, ZSM-22, ZSM-23, ZSM-35, ZSM-57 and MCM-22, wherein the catalyst also comprises aluminum molybdate;
- and
- (b) contacting said catalyst with an atmosphere containing steam at a temperature of about 200° C. to about 450° C. and a pressure of at least 1000 kPa to reduce the amount of aluminum molybdate in said catalyst, wherein the amount of aluminum present as aluminum molybdate in said catalyst is less than 2700 ppm by weight;
- said catalyst characterized by the formation of aluminium molybdate during dehydrocyclization of methane to benzene,
- wherein said catalyst's exposure during dehydrocyclization and regeneration has been limited to not more than 100 wt ppm molecular oxygen and/or ozone at a temperature not in excess of 650° C. for a cumulative time not greater than 10 hours.
Dependencies are inferred from the claim text.