Method for producing methyl tert-butyl ether and fuel composition containing the same

Claim 1

A method for continuously producing methyl tert-butyl ether by reacting methyl alcohol and isobutylene in the presence of an acidic cation exchange resin comprising the steps of (A) allowing isobutylene and methyl alcohol to react with each other by continuously passing an isobutylene-containing hydrocarbon mixture and methyl alcohol through a fixed bed filled with a stongly acidic cation-exchange resin particles of 0.2 to 10 mm in mean grain diameter, at a temperature of 0° to 100° C., a pressure of 1 to 50 atmospheres and a liquid space velocity of 0.1 to 50 (1/hr), the molar ration of isobutylene in said mixture to said methyl alcohol being in the range of 1:0.6 to 1:1.4, (B) dividing the effluent from the reaction of step (A) into first and second parts in which the weight ratio of said first part to said second part is in the range from 1:3 to 1:15; (C) recycling said second part to the fixed bed in step (A); (D) passing said first part through a fixed bed filled with a water-insoluble, solid, particulate acid-neutralizing agent of 0.1 to 10 mm in mean grain diameter, at 0 to 100° C.; (E) introducing the neutralized first part into a flashing tower to flash-remove unreacted hydrocarbon and to recover a methyl tert-butyl ether containing mixture from the bottom of said flashing tower and (F) distilling said methyl tert-butyl ether-containing mixture with a multi-stage distillation column to remove an azeotropic mixture of methyl tert-butyl ether and methyl alcohol from the top of said distillation column and to recycle said azeotropic mixture for reuse in step (A), thereby obtaining methyl tert-butyl ether from the bottom of said distillation column.

Claim 2

A method for continuously producing methyl tert-butyl ether by reacting methyl alcohol and isobutylene in the presence of an acidic cation exchange resin comprising the steps of (A) allowing isobutylene and methyl alcohol to react with each other by continuously passing an isobutylene-containing hydrocarbon mixture and methyl alcohol through a fixed bed filled with a stongly acidic cation-exchange resin particles of 0.2 to 10 mm in mean grain diameter, at a temperature of 0° to 100° C., a pressure of 1 to 50 atmospheres and a liquid space velocity of 0.1 to 50 (1/hr), the molar ration of isobutylene in said mixture to said methyl alcohol being in the range of 1:0.6 to 1:1.4, (B) dividing the effluent from the reaction of step (A) into first and second parts in which the weight ratio of said first part to said second part is in the range from 1:3 to 1:15; (C) recycling said second part to the fixed bed in step (A); (D) passing said first part through a fixed bed filled with a water-insoluble, solid, particulate acid-neutralizing agent of 0.1 to 10 mm in mean grain diameter, at 0 to 100° C.; (E) introducing the neutralized first part into a flashing tower to flash-remove unreacted hydrocarbon and to recover a methyl tert-butyl ether containing mixture from the bottom of said flashing tower and (F) distilling said methyl tert-butyl ether-containing mixture with a multi-stage distillation column to remove an azeotropic mixture of methyl tert-butyl ether and methyl alcohol from the top of said distillation column and to recycle said azeotropic mixture for reuse in step (A), thereby obtaining methyl tert-butyl ether from the bottom of said distillation column.