Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
259 words
A process for preparing an acetic acid product selected from the group consisting of acetic acid, methyl acetate, acetic anhydride and mixtures thereof by conversion of a synthesis gas comprising hydrogen and carbon oxides, said process comprising the steps of: (i) introducing said synthesis gas into a first reactor at a pressure of 5-200 bar and a temperature of 150°-400° C., and converting said synthesis gas therein in the gas phase into methanol and dimethyl ether in the presence of a catalyst selected from the group consisting of a mixture of CuO-ZnO-Al 2 O 3 having a composition of about 60 atom% Cu, 25 atom% Zn and 15 atom% Al, and a zeolite so as to obtain a mol proportion 0.1:1 to 3:1 of carbon monoxide to methanol plus dimethyl ether, said mol proportion being defined by the expression CO/(CH 3 OH+2 CH 3 OCH 3 ), and then (ii) carbonylating the methanol and dimethyl ether formed in step (i) together by passing the effluent from the first reactor to a second reactor and converting methanol and dimethyl ether therein in a fluid phase to said acetic acid product at a pressure of 1-800 bar and a temperature of 100°-500° C. in the presence of a catalyst, the catalyst including a rhodium compound as a catalytic active material and the catalyst being promoted with methyl iodide and then (iii) recovering from effluent of said second reactor at least one product stream, the product stream consisting of either the acetic acid, the methyl acetate, the acetic anhydride or mixtures thereof.
Claim 2
Dependent Claim
259 words
A process for preparing an acetic acid product selected from the group consisting of acetic acid, methyl acetate, acetic anhydride and mixtures thereof by conversion of a synthesis gas comprising hydrogen and carbon oxides, said process comprising the steps of: (i) introducing said synthesis gas into a first reactor at a pressure of 5-200 bar and a temperature of 150°-400° C., and converting said synthesis gas therein in the gas phase into methanol and dimethyl ether in the presence of a catalyst selected from the group consisting of a mixture of CuO-ZnO-Al 2 O 3 having a composition of about 60 atom% Cu, 25 atom% Zn and 15 atom% Al, and a zeolite so as to obtain a mol proportion 0.1:1 to 3:1 of carbon monoxide to methanol plus dimethyl ether, said mol proportion being defined by the expression CO/(CH 3 OH+2 CH 3 OCH 3 ), and then (ii) carbonylating the methanol and dimethyl ether formed in step (i) together by passing the effluent from the first reactor to a second reactor and converting methanol and dimethyl ether therein in a fluid phase to said acetic acid product at a pressure of 1-800 bar and a temperature of 100°-500° C. in the presence of a catalyst, the catalyst including a rhodium compound as a catalytic active material and the catalyst being promoted with methyl iodide and then (iii) recovering from effluent of said second reactor at least one product stream, the product stream consisting of either the acetic acid, the methyl acetate, the acetic anhydride or mixtures thereof.
Claim 3
Dependent Claim
24 words
The process according to claim 1, wherein the conversion in step (ii) is carried out at substantially the same pressure as in step (i).
Claim 4
Dependent Claim
51 words
The process according to claim 1, wherein said synthesis gas is converted in said first reactor so as to obtain a mol proportion of carbon dioxide to methanol plus dimethyl ether in the effluent from said first reactor which is an optimal mol proportion for the acetic acid product or products.
Claim 5
Dependent Claim
47 words
The process according to claim 2, wherein said synthesis gas is converted in said first reactor so that a mol proportion of carbon monoxide plus dimethyl ether of approximately 1 is maintained in the first reactor and acetic acid and/or anhydride is predominantly formed by the process.
Claim 6
Dependent Claim
47 words
The process according to claim 3, wherein said synthesis gas is converted in said first reactor so that a mol proportion of carbon monoxide to methanol plus dimethyl ether of approximately 0.5 is maintained in the first reactor and methyl acetate is predominantly formed by the process.
Claim 7
Dependent Claim
48 words
The process according to claim 1, further comprising the step of adding H 2 O to the effluent of the first reactor in an amount such that the effluent of the first reactor has a mol proportion of H 2 O to dimethyl ether of up to 10.