Catalyst for conversion of methanol to hydrocarbons
AssigneeExxonMobil Research and Engineering Company
InventorsBrett Loveless, Christine N. Elia, Stephen J. McCarthy
Life of this patent
Estimating the term…
Abstract
Methods are provided for performing a conversion reaction using a catalyst steamed under mild steaming conditions. Steaming a conversion catalyst under mild steaming conditions can provide an increased conversion activity and/or an increased run length for the catalyst during conversion of an oxygenate feed to aromatic hydrocarbons, such as benzene or xylene. Suitable conversion catalysts can include alumina bound catalysts including a medium pore molecular sieve.
Claims21
A method of converting a feed to form olefins and aromatics, comprising:
- steaming a catalyst in the presence of at least 0.01 atm (1 kPa) of water at a temperature of about 450° F. (about 221° C.) to about 700° F. (about 371° C.) for at least about 0.25 hours to form a steamed catalyst, the catalyst comprising a molecular sieve having at least one 10-member ring channel and having no ring channels larger than a 10-member ring channel;
- and
- subsequently exposing a feed comprising at least about 30 wt % of methanol, dimethyl ether, or a combination thereof to the steamed catalyst under effective conversion conditions to form a conversion effluent comprising ethylene, propylene, and at least one aromatic, the effective conversion conditions including a temperature of about 200° C. to about 700° C.,
- the steamed catalyst having a cycle length under the effective conversion conditions that is at least about 15% greater than a cycle length under the effective conversion conditions for the catalyst prior to steaming, and/or the steamed catalyst having an alpha value that is at least about 10 greater than an alpha value for the catalyst prior to steaming.
A method of converting an oxygenate feed to form hydrocarbons, comprising:
- steaming a catalyst in the presence of at least 0.9 atm (90 kPa) of water at a temperature of about 450° F. (about 221° C.) to about 650° F. (about 343° C.) for about 0.25 hours to about 16 hours to form a steamed catalyst, the catalyst comprising a molecular sieve having at least one 8-member ring channel, 10-member ring channel, or 12-member ring channel and having no ring channels larger than a 12-member ring channel;
- and
- subsequently exposing a feed comprising at least about 50 wt % of methanol, dimethyl ether, or a combination thereof to the steamed catalyst under effective conversion conditions to form a conversion effluent comprising one or more hydrocarbons, the effective conversion conditions including a temperature of about 200° C. to about 700° C.,
- the steamed catalyst having a cycle length under the effective conversion conditions that is at least about 15% greater than a cycle length under the effective conversion conditions for the catalyst prior to steaming, and/or the steamed catalyst having an alpha value that is at least about 10 greater than an alpha value for the catalyst prior to steaming.
Dependencies are inferred from the claim text.