Abstract: The present invention relates to a process for separating at least one propylene glycol from a mixture (M) comprising water and said propylene glycol, said process comprising (I) evaporating the mixture in at least two evaporation and/or distillation stages at decreasing operating pressures of the evaporators and/or distillation columns obtaining mixture (M?) and mixture (M?); (II) separating the mixture (M?) obtained in (I) in at least one further distillation step, obtaining a mixture (M-I) comprising at least 70 wt.-% of water and a mixture (M-II) comprising less than 30 wt.-% of water.

Abstract: The invention relates to a process for the epoxidation of an olefin comprising (a) reacting the olefin with hydrogen peroxide in the presence of methanol as solvent in at least two reaction stages to obtain a mixture (M-a) comprising olefin oxide, unreacted olefin, methanol and water, wherein between at least two reaction stages, olefin oxide is separated by distillation; (b) separating unreacted olefin from the mixture (M-a) by distillation to obtain a mixture (M-bi) comprising at least 80 wt.-% of olefin and a mixture (M-bii) comprising methanol, water and at least 7 wt.-% of olefin oxide; (c) separating olefin oxide from the mixture (M-bii) in at least one distillation stage to obtain a mixture (M-ci) comprising at least 99 wt.-% of olefin oxide and a mixture (M-cii) comprising water and at least 55 wt.-% of methanol; (d) separating methanol from the mixture (M-cii) in at least one distillation stage to obtain a mixture (M-di) comprising at least 85 wt.-% of methanol and up to 10 wt.

Abstract: A process for producing epoxides, the process including: (a) feeding at least one aqueous alkali and at least one halohydrin to a reactive distillation column, wherein the reactive distillation column includes a feed zone, a top zone disposed above the feed zone, and a bottom zone disposed below the feed zone; (b) concurrently in the reactive distillation column: (i) reacting at least a portion of the halohydrin with the alkali to form an epoxide; and (ii) stripping water and the epoxide from a basic aqueous residue; (c) recovering the water and the epoxide from the reactive distillation column as an overheads fraction; (d) condensing and phase separating the overheads fraction to form an organic overheads fraction including the epoxide and an aqueous overheads fraction including water; and (e) maintaining a liquid holdup per plate in the feed zone at a residence time of 10 seconds or less.

Abstract: A process for producing epoxides, the process including: (a) feeding at least one aqueous alkali and at least one halohydrin to a reactive distillation column; (b) concurrently in the reactive distillation column: (i) reacting at least a portion of the halohydrin with the alkali to form an epoxide; and (ii) stripping water and the epoxide from a basic aqueous residue; (c) recovering the water and the epoxide from the reactive distillation column as an overheads fraction; and, (d) condensing and phase separating the overheads fraction at a temperature of 50° C. or less to form an organic overheads fraction including the epoxide and an aqueous overheads fraction including water.

Abstract: A method of separating propylene oxide from a mixture (M) comprising propylene oxide and methanol, said method comprising: (i) introducing said mixture (M) into an extractive distillation column; (ii) additionally introducing an extracting solvent into said extractive distillation column; (iii) distilling propylene oxide overhead from said extractive distillation column as top stream; (iv) withdrawing a bottoms stream from said extractive distillation column; (v) compressing the top stream obtained overhead in (iii) by means of at least one compressor to give a compressed vapor.

Abstract: The invention relates to a process for the epoxidation of an olefin comprising (a) reacting the olefin with hydrogen peroxide in the presence of methanol as solvent in at least two reaction stages to obtain a mixture (M-a) comprising olefin oxide, unreacted olefin, methanol and water, wherein between at least two reaction stages, olefin oxide is separated by distillation; (b) separating unreacted olefin from the mixture (M-a) by distillation to obtain a mixture (M-bi) comprising at least 80 wt.-% of olefin and a mixture (M-bii) comprising methanol, water and at least 7 wt.-% of olefin oxide; (c) separating olefin oxide from the mixture (M-bii) in at least one distillation stage to obtain a mixture (M-ci) comprising at least 99 wt.-% of olefin oxide and a mixture (M-cii) comprising water and at least 55 wt.-% of methanol; (d) separating methanol from the mixture (M-cii) in at least one distillation stage to obtain a mixture (M-di) comprising at least 85 wt.-% of methanol and up to 10 wt.

Abstract: A process for producing epoxides, the process including: (a) feeding at least one aqueous alkali and at least one halohydrin to a reactive distillation column; (b) concurrently in the reactive distillation column: (i) reacting at least a portion of the halohydrin with the alkali to form an epoxide; and (ii) stripping water and the epoxide from a basic aqueous residue; (c) recovering the water and the epoxide from the reactive distillation column as an overheads fraction; and, (d) condensing and phase separating the overheads fraction at a temperature of 50° C. or less to form an organic overheads fraction including the epoxide and an aqueous overheads fraction including water.

Abstract: A process for producing epoxides, the process including: (a) feeding at least one aqueous alkali and at least one halohydrin to a reactive distillation column, wherein the reactive distillation column includes a feed zone, a top zone disposed above the feed zone, and a bottom zone disposed below the feed zone; (b) concurrently in the reactive distillation column: (i) reacting at least a portion of the halohydrin with the alkali to form an epoxide; and (ii) stripping water and the epoxide from a basic aqueous residue; (c) recovering the water and the epoxide from the reactive distillation column as an overheads fraction; (d) condensing and phase separating the overheads fraction to form an organic overheads fraction including the epoxide and an aqueous overheads fraction including water; and (e) maintaining a liquid holdup per plate in the feed zone at a residence time of 10 seconds or less.

Abstract: A process of separating a purified propylene oxide from a crude epoxidation product produced, preferably, in an epoxidation reaction of propylene with hydrogen peroxide. The process involves removing bulk water, bulk methanol, and unreacted propylene from the crude epoxidation product and thereafter subjecting the resulting propylene oxide product to extractive distillation with water as an extraction solvent. Under distillation conditions, including a bottoms temperature of greater than about 55° C. and less than about 75° C., an overhead or side-cut distillate stream containing a purified propylene oxide is obtained with low yield loss of propylene oxide to propylene glycols and other glycol heavies. The purified propylene oxide can be further purified in a finishing distillation to obtain propylene oxide meeting commercial grade purity requirements.

Abstract: A method of separating propylene oxide from a mixture (M) comprising propylene oxide and methanol, said method comprising: (i) introducing said mixture (M) into an extractive distillation column; (ii) additionally introducing an extracting solvent into said extractive distillation column; (iii) distilling propylene oxide overhead from said extractive distillation column as top stream; (iv) withdrawing a bottoms stream from said extractive distillation column; (v) compressing the top stream obtained overhead in (iii) by means of at least one compressor to give a compressed vapor.

Abstract: The present invention relates to a process for separating at least one propylene glycol from a mixture (M) comprising water and said propylene glycol, said process comprising (I) evaporating the mixture in at least two evaporation and/or distillation stages at decreasing operating pressures of the evaporators and/or distillation columns obtaining mixture (M?) and mixture (M?); (II) separating the mixture (M?) obtained in (I) in at least one further distillation step, obtaining a mixture (M-I) comprising at least 70 wt.-% of water and a mixture (M-II) comprising less than 30 wt.-% of water.

Abstract: A method of separating propylene oxide from a mixture (M) comprising 5 to 50 percent by weight propylene oxide and 50 to 85 percent by weight methanol, said method comprising (i) introducing said mixture (M) into an extractive distillation column; (ii) additionally introducing a polar solvent into said extractive distillation column; (iii) distilling propylene oxide overhead from said extractive distillation column at a bottoms temperature of from 40 to 70° C. and at a pressure of from 300 to 750 mbar.

Abstract: A method of separating propylene oxide from a mixture (M) comprising 5 to 50 percent by weight propylene oxide and 50 to 85 percent by weight methanol, said method comprising (i) introducing said mixture (M) into an extractive distillation column; (ii) additionally introducing a polar solvent into said extractive distillation column; (iii) distilling propylene oxide overhead from said extractive distillation column at a bottoms temperature of from 40 to 70° C. and at a pressure of from 300 to 750 mbar.

Abstract: The present invention relates to a method of separating an olefin from a gas stream, said gas stream comprising the olefin and at least one other component, said method comprising (i) compressing and cooling the gas stream; (ii) separating the olefin from the gas stream by absorbing the olefin in an absorbent; (iii) separating the olefin from the absorbent by desorption; wherein compressing or cooling or compressing and cooling in (i) is carried out at least twice.

Abstract: The invention relates to a process for the epoxidation of an olefin comprising (a) reacting the olefin with hydrogen peroxide in the presence of methanol as solvent in at least two reaction stages to obtain a mixture (M-a) comprising olefin oxide, unreacted olefin, methanol and water, wherein between at least two reaction stages, olefin oxide is separated by distillation; (b) separating unreacted olefin from the mixture (M-a) by distillation to obtain a mixture (M-bi) comprising at least 80 wt.-% of olefin and a mixture (M-bii) comprising methanol, water and at least 7 wt.-% of olefin oxide; (c) separating olefin oxide from the mixture (M-bii) in at least one distillation stage to obtain a mixture (M-ci) comprising at least 99 wt.-% of oletin oxide and a mixture (M-cii) comprising water and at least 55 wt.-% of methanol; (d) separating methanol from the mixture (M-cii) in at least one distillation stage to obtain a mixture (M-di) comprising at least 85 wt.-% of methanol and up to 10 wt.

Abstract: A process of separating a purified propylene oxide from a crude epoxidation product produced, preferably, in an epoxidation reaction of propylene with hydrogen peroxide. The process involves removing bulk water, bulk methanol, and unreacted propylene from the crude epoxidation product and thereafter subjecting the resulting propylene oxide product to extractive distillation with water as an extraction solvent. Under distillation conditions, including a bottoms temperature of greater than about 55° C. and less than about 75° C., an overhead or side-cut distillate stream containing a purified propylene oxide is obtained with low yield loss of propylene oxide to propylene glycols and other glycol heavies. The purified propylene oxide can be further purified in a finishing distillation to obtain propylene oxide meeting commercial grade purity requirements.

Abstract: A method of separating propylene oxide from a mixture (M) comprising 5 to 50 percent by weight propylene oxide and 50 to 85 percent by weight methanol, said method comprising (i) introducing said mixture (M) into an extractive distillation column; (ii) additionally introducing a polar solvent into said extractive distillation column; (iii) distilling propylene oxide overhead from said extractive distillation column at a bottoms temperature of from 40 to 70° C. and at a pressure of from 300 to 750 mbar.

Abstract: A method of separating propylene oxide from a mixture (M) comprising propylene oxide and methanol, said method comprising (i) introducing said mixture (M) into an extractive distillation column; (ii) additionally introducing an extracting solvent into said extractive distillation column; (iii) distilling propylene oxide overhead from said extractive distillation column as top stream; (iv) withdrawing a bottoms stream from said extractive distillation column; (v) compressing the top stream obtained overhead in (iii) by means of at least one compressor to give a compressed vapor.

Abstract: The present invention relates to a method of separating an olefin from a gas stream, said gas stream comprising the olefin and at least one other component, said method comprising (i) compressing and cooling the gas stream; (ii) separating the olefin from the gas stream by absorbing the olefin in an absorbent; (iii) separating the olefin from the absorbent by desorption; wherein compressing or cooling or compressing and cooling in (i) is carried out at least twice.