Processes and systems for separating a mixture of three or more chemical components into multiple product streams each enriched in one of the components are provided herein. In some aspects, the present invention relates to processes for the separation of a chemical mixture including at least a heavy key component, an intermediate key component, and a light key component to form a product stream enriched in the light key component, a product stream enriched in the intermediate key component, and a product stream enriched in the heavy key component. Systems described herein may include one or more thermally coupled distillation columns including, for example, a dividing wall column, or a plurality of distillation columns arranged in a thermally integrated configuration.

Provided is a method of preparing isopropyl alcohol (IPA) including a purification step using a plurality of column, the method allows recovery of IPA with high purity, by separating water first before removing NPA and applying a dividing wall column (DWC) to perform both separation of IPA and NPA and separation of water and high-boiling point organic substances.

Provided is a method of preparing isopropyl alcohol (IPA) including a purification step using a plurality of column, the method allows recovery of IPA with high purity, by separating water first before removing NPA and applying a dividing wall column (DWC) to perform both separation of IPA and NPA and separation of water and high-boiling point organic substances.

Provided is a method of preparing isopropyl alcohol (IPA) including a purification step using a plurality of column, the method allows recovery of IPA with high purity, by separating water first before removing NPA and applying a dividing wall column (DWC) to perform both separation of IPA and NPA and separation of water and high-boiling point organic substances.

The invention provides a process for separating monoethylene glycol from a mixture comprising monoethylene glycol and 1,2-butanediol, said process comprising the steps of: a. providing a first stream comprising monoethylene glycol and 1,2-butanediol to a first distillation zone operated at a first pressure and under conditions to remove a first bottoms stream comprising 1,2-butanediol and to remove a first azeotrope of monoethylene glycol and 1,2-butanediol from the first distillation zone as a first overheads stream; b. withdrawing said first overheads stream from said first distillation zone; and c. providing said first overheads stream to a second distillation zone operated at a second pressure higher than said first pressure and under conditions to remove a second bottoms stream comprising monoethylene glycol and providing a second azeotrope of monoethylene glycol and 1,2-butanediol as a second overheads stream; d. withdrawing said second overheads stream from the second distillation zone and providing it to the first distillation zone as at least a portion of the first stream comprising monoethylene glycol and 1,2-butanediol, e. wherein the mixture comprising monoethylene glycol and 1,2-butanediol is initially provided to at least one of the first distillation zone and the second distillation zone.

The invention provides a process for separating monoethylene glycol from a mixture comprising monoethylene glycol and 1,2-butanediol, said process comprising the steps of: a. providing a first stream comprising monoethylene glycol and 1,2-butanediol to a first distillation zone operated at a first pressure and under conditions to remove a first bottoms stream comprising 1,2-butanediol and to remove a first azeotrope of monoethylene glycol and 1,2-butanediol from the first distillation zone as a first overheads stream; b. withdrawing said first overheads stream from said first distillation zone; and c. providing said first overheads stream to a second distillation zone operated at a second pressure higher than said first pressure and under conditions to remove a second bottoms stream comprising monoethylene glycol and providing a second azeotrope of monoethylene glycol and 1,2-butanediol as a second overheads stream; d. withdrawing said second overheads stream from the second distillation zone and providing it to the first distillation zone as at least a portion of the first stream comprising monoethylene glycol and 1,2-butanediol, e. wherein the mixture comprising monoethylene glycol and 1,2-butanediol is initially provided to at least one of the first distillation zone and the second distillation zone.

The invention provides a process for separating monoethylene glycol from a mixture comprising monoethylene glycol and 1,2-butanediol, said process comprising the steps of: a. providing a first stream comprising monoethylene glycol and 1,2-butanediol to a first distillation zone operated at a first pressure and under conditions to remove a first bottoms stream comprising 1,2-butanediol and to remove a first azeotrope of monoethylene glycol and 1,2-butanediol from the first distillation zone as a first overheads stream; b. withdrawing said first overheads stream from said first distillation zone; and c. providing said first overheads stream to a second distillation zone operated at a second pressure higher than said first pressure and under conditions to remove a second bottoms stream comprising monoethylene glycol and providing a second azeotrope of monoethylene glycol and 1,2-butanediol as a second overheads stream; d. withdrawing said second overheads stream from the second distillation zone and providing it to the first distillation zone as at least a portion of the first stream comprising monoethylene glycol and 1,2-butanediol, e. wherein the mixture comprising monoethylene glycol and 1,2-butanediol is initially provided to at least one of the first distillation zone and the second distillation zone.

The invention provides a process for refining bio-based propylene glycol, wherein impurities having boiling points close to that of propylene glycol are separated. In this process, C.sub.5-C.sub.20 oleophilic alcohol compounds, C.sub.5-C.sub.20 alkanes and/or C.sub.4-C.sub.20 oleophilic ketone compounds are subjected to azeotropism as an azeotropic solvent together with the bio-based propylene glycol to obtain an azeotrope containing propylene glycol. Then the azeotropic solvent in the azeotrope is separated to obtain a crude propylene glycol which is further purified to obtain propylene glycol.

The invention provides a process for refining bio-based propylene glycol, wherein impurities having boiling points close to that of propylene glycol are separated. In this process, C.sub.5-C.sub.20 oleophilic alcohol compounds, C.sub.5-C.sub.20 alkanes and/or C.sub.4-C.sub.20 oleophilic ketone compounds are subjected to azeotropism as an azeotropic solvent together with the bio-based propylene glycol to obtain an azeotrope containing propylene glycol. Then the azeotropic solvent in the azeotrope is separated to obtain a crude propylene glycol which is further purified to obtain propylene glycol.

Method for separating ethylene glycol (EG) and ethylene glycol diacetate (EGDA) with sulfolane entrainer, including: obtaining EG and a mixture of EGDA and sulfolane through separating a mixture of EG and EGDA under an action of sulfolane by an extractive distillation tower; obtaining EGDA and sulfolane through separating the mixture of the EGDA and the sulfolane by an entrainer recovery tower; and obtaining recycled sulfolane through cooling the sulfolane by a heat exchanger, and mixing the recycled sulfolane with fresh sulfolane and circulating into the extractive distillation tower for recycling. Through the method, a yield of the EG is greater than or equal to 99.50% and a mass purity of the EG is greater than or equal to 99.50%, and a yield of the EGDA is greater than or equal to 99.80% and a mass purity of the EGDA is greater than or equal to 99.90%.