Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
179 words
A process of producing methyl tertiary butyl ether, comprising reacting isobutylene and methanol using a mixture (A) of hydrocarbons each having 4 carbon atoms and containing isobutylene and methanol as starting materials, in a reaction zone (2) containing an acidic ion exchange resin, and transferring the resulting reaction mixture to a distillation column (3) wherein it is distilled so as to separate methyl tertiary butyl ether (C) from the unreacted 4C hydrocarbon mixture, characterised in that (a) a mixture of the 4C hydrocarbon mixture produced as a distillate from the top of the distillation column and methanol as an azeotropic distillate is contacted with water (E) in a second extraction step (4) to wash and extract the methanol with water, and (b) the water (F) containing the extracted methanol is then contacted with said 4C hydrocarbon mixture (A) containing isobutylene which is fed to the reaction zone (2) in a first extraction step (1) upstream of the reaction zone, to thereby transfer a part of the methanol in the.methanol-containing water (F) into the feed hydrocarbon mixture (A) .by extraction.
Claim 2
Dependent Claim
179 words
A process of producing methyl tertiary butyl ether, comprising reacting isobutylene and methanol using a mixture (A) of hydrocarbons each having 4 carbon atoms and containing isobutylene and methanol as starting materials, in a reaction zone (2) containing an acidic ion exchange resin, and transferring the resulting reaction mixture to a distillation column (3) wherein it is distilled so as to separate methyl tertiary butyl ether (C) from the unreacted 4C hydrocarbon mixture, characterised in that (a) a mixture of the 4C hydrocarbon mixture produced as a distillate from the top of the distillation column and methanol as an azeotropic distillate is contacted with water (E) in a second extraction step (4) to wash and extract the methanol with water, and (b) the water (F) containing the extracted methanol is then contacted with said 4C hydrocarbon mixture (A) containing isobutylene which is fed to the reaction zone (2) in a first extraction step (1) upstream of the reaction zone, to thereby transfer a part of the methanol in the.methanol-containing water (F) into the feed hydrocarbon mixture (A) .by extraction.
Claim 3
Dependent Claim
43 words
A process as claimed in Claim 1, wherein the first and second extraction steps are carried out at a temperature of from 20° to 70°C under such a pressure that the contents in the extraction step can be maintained in a liquid state.
Claim 4
Dependent Claim
25 words
A process as claimed in Claim 2, wherein the first and second extraction steps are carried out at a temperature of from 30°C to 60°C.
Claim 5
Dependent Claim
38 words
A process as claimed in Claim 1, 2 or 3, wherein the proportion of water to be fed to the second extraction step to the unreacted hydrocarbon is from 1 : 3 to 1 : 30 by weight.
Claim 6
Dependent Claim
28 words
A process as claimed in Claim 4, wherein said proportion of water in the second extraction step is from 1 : 7 to 1 : 20 by weight.
Claim 7
Dependent Claim
38 words
A process as claimed in any preceding claim, wherein methanol is fed to the reaction zone (2) in an amount of from 0.9 to 1.6 moles per mole of isobutylene in the hydrocarbon mixture of 4 carbon atoms.
Claim 8
Dependent Claim
26 words
A process as claimed in Claim 6, wherein said amount of methanol fed is 0.95 to 1.3 moles per mole of isobutylene in the hydrocarbon mixture.
Claim 9
Dependent Claim
25 words
A process as claimed in any preceding claim, wherein methanol (B) is added to the hydrocarbon mixture phase (F) to which methanol has been transferred.