A method for preparing methyl formate in which a raw material containing formaldehyde, methanol and/or dimethyl ether is introduced into a first reaction zone to come into contact with a catalyst A, and a component I is obtained by separation, the component I is introduced into a second reaction zone to come into contact with a catalyst B so as to obtain, by separation, methyl formate as a product, dimethyl ether that is returned to the first reaction zone and a component II that is returned to the second reaction zone, the catalysts have a long service life, the reaction conditions are mild, and the utilization rate of the raw material is high, thus enabling a continuous production for large-scale industrial application.

Method for preparing methyl formate and coproducing dimethyl ether by reacting a formaldehyde and methanol raw material (molar ratio range of 1:4 to 1:0.05) in a First Reaction Region at ranges from 50° C. to 100° C. with Catalyst A resulting in post-reaction material separated into Constituent I. Reacting Constituent I in a Second Reaction Region at ranges from 50° C. to 200° C. and from 0.1 MPa to 10 MPa with Catalyst B resulting in post-reaction material, which is separated into methyl formate, dimethyl ether and Constituent II. At least 1% of dimethyl ether is product, and recycling the rest to the First Reaction Region. Constituent II is recycled to the Second Reaction Region. Each component is gaseous phase and/or liquid phase, independently. The method shows long catalyst life, mild reaction condition, high utilization ratio of raw materials, continuous production and large scale industrial application potential.

Method for preparing methyl formate and coproducing dimethyl ether by reacting a formaldehyde and methanol raw material (molar ratio range of 1:4 to 1:0.05) in a First Reaction Region at ranges from 50° C. to 100° C. with Catalyst A resulting in post-reaction material separated into Constituent I. Reacting Constituent I in a Second Reaction Region at ranges from 50° C. to 200° C. and from 0.1 MPa to 10 MPa with Catalyst B resulting in post-reaction material, which is separated into methyl formate, dimethyl ether and Constituent II. At least 1% of dimethyl ether is product, and recycling the rest to the First Reaction Region. Constituent II is recycled to the Second Reaction Region. Each component is gaseous phase and/or liquid phase, independently. The method shows long catalyst life, mild reaction condition, high utilization ratio of raw materials, continuous production and large scale industrial application potential.

Provided is a method for directly preparing dimethyl ether by synthesis gas, the method comprises: the synthesis gas is passed through a reaction zone carrying a catalyst, and reacted under the reaction conditions sufficient to convert at least a portion of the raw materials to obtain the reaction effluent comprising dimethyl ether; and the dimethyl ether is separated from the reaction effluent, wherein the catalyst is zinc aluminum spinel oxide. In the present invention, only one zinc aluminum spinel oxide catalyst is used, which can make the synthesis gas to highly selectively form dimethyl ether, the catalyst has good stability and can be regenerated. The method of the present invention realizes the production of dimethyl ether in one step by the synthesis gas, and reduces the large energy consumption problem caused by step-by-step production.

Provided is a method for directly preparing dimethyl ether by synthesis gas, the method comprises: the synthesis gas is passed through a reaction zone carrying a catalyst, and reacted under the reaction conditions sufficient to convert at least a portion of the raw materials to obtain the reaction effluent comprising dimethyl ether; and the dimethyl ether is separated from the reaction effluent, wherein the catalyst is zinc aluminum spinel oxide. In the present invention, only one zinc aluminum spinel oxide catalyst is used, which can make the synthesis gas to highly selectively form dimethyl ether, the catalyst has good stability and can be regenerated. The method of the present invention realizes the production of dimethyl ether in one step by the synthesis gas, and reduces the large energy consumption problem caused by step-by-step production.

A process separates pure components from a product mixture produced by a one-step dimethyl ether synthesis reactor. The product mixture is scrubbed with pure dimethyl ether followed by scrubbing with aqueous methanol solvent in two absorption columns to reduce CO.sub.2 level and to minimize methanol and dimethyl ether loss with the recovered unconverted synthetic gas. The pure water or aqueous methanol is mixed with the vapor stream of CO.sub.2 separation distillation. Dimethyl ether, methanol and water mixture are separated. A scheme for separation of methanol and water mixture minimizes the size, energy and cost of separation. The process can be cost-effective, energy-efficient, environment-friendly and readily-miniaturized.

A process separates pure components from a product mixture produced by a one-step dimethyl ether synthesis reactor. The product mixture is scrubbed with pure dimethyl ether followed by scrubbing with aqueous methanol solvent in two absorption columns to reduce CO.sub.2 level and to minimize methanol and dimethyl ether loss with the recovered unconverted synthetic gas. The pure water or aqueous methanol is mixed with the vapor stream of CO.sub.2 separation distillation. Dimethyl ether, methanol and water mixture are separated. A scheme for separation of methanol and water mixture minimizes the size, energy and cost of separation. The process can be cost-effective, energy-efficient, environment-friendly and readily-miniaturized.

The present invention relates to an intensification of the synthetic process for the preparation of dialkyl ether from alcohol by using a conical fixed bed reactor integrated with distillation coupled conical polishing reactor.

The present invention relates to an intensification of the synthetic process for the preparation of dialkyl ether from alcohol by using a conical fixed bed reactor integrated with distillation coupled conical polishing reactor.

A process for dehydrating methanol to dimethyl ether product in the presence of a catalyst and a promoter, wherein the catalyst is at least one aluminosilicate zeolite, wherein:—the aluminosilicate zeolite is selected from: (i) a zeolite having a 2-dimensional framework structure comprising at least one channel having a 10-membered ring, and having a maximum free sphere diameter of at least 4.8 Angstroms; (ii) a zeolite having a 3-dimensional framework structure comprising at least one channel having a 10-membered ring; or (iii) a zeolite comprising at least one channel having a 12-membered ring;—the promoter is selected from one or more compounds of Formula I: (I) wherein Y is selected from a C.sub.1-C.sub.4 hydrocarbyl substituent, and wherein each of X and any or all of the Z's may independently be selected from hydrogen, halide, a substituted or unsubstituted hydrocarbyl substituent, or a compound of the formula —CHO, —CO.sub.2R, —COR, or —OR, where R is hydrogen or a substituted or unsubstituted hydrocarbyl substituent, and wherein the molar ratio of promoter to methanol is maintained at less than 1.

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