A method of preparing isopropyl alcohol including: supplying a feed stream including a propylene monomer and water to a reaction unit and reacting the propylene monomer and water to produce a reaction product including isopropyl alcohol, the propylene monomer, and the water; supplying a first discharge stream including a gaseous reaction product and a second discharge stream including a liquid reaction product from the reaction unit to a stripper; and in the stripper, circulating an upper discharge stream including the propylene monomer to the reaction unit and supplying a lower discharge stream including water and isopropyl alcohol to an isopropyl alcohol purification unit, where the first discharge stream is condensed by a first heat exchanger and supplied as a liquid phase to the stripper.

A method of preparing isopropyl alcohol including: supplying a feed stream including a propylene monomer and water to a reaction unit and reacting the propylene monomer and water to produce a reaction product including isopropyl alcohol, the propylene monomer, and the water; supplying a first discharge stream including a gaseous reaction product and a second discharge stream including a liquid reaction product from the reaction unit to a stripper; and in the stripper, circulating an upper discharge stream including the propylene monomer to the reaction unit and supplying a lower discharge stream including water and isopropyl alcohol to an isopropyl alcohol purification unit, where the first discharge stream is condensed by a first heat exchanger and supplied as a liquid phase to the stripper.

A method of preparing isopropyl alcohol including: supplying a feed stream including a propylene monomer and water to a reaction unit and reacting the propylene monomer and water to produce a reaction product including isopropyl alcohol, the propylene monomer, and the water; supplying a first discharge stream including a gaseous reaction product and a second discharge stream including a liquid reaction product from the reaction unit to a stripper; and in the stripper, circulating an upper discharge stream including the propylene monomer to the reaction unit and supplying a lower discharge stream including water and isopropyl alcohol to an isopropyl alcohol purification unit, where the first discharge stream is condensed by a first heat exchanger and supplied as a liquid phase to the stripper.

The present disclosure provides processes and systems for heat integration in ethanol production. In one embodiment, a feed mixture is distilled with one or more distillation units to remove at least a portion of the water, and form a distillation unit bottom stream, a vaporous overhead stream, and a fusel oil stream. Molecular sieve units are regenerated by vacuum or a combination of vacuum and optionally a portion of the product stream to form one or more regenerate streams. A feed tank is configured to receive at least one selected from a condensed portion of the regenerate streams and a portion of a vaporous depressure stream, to form a feed stream. The energy contained in the depressure vapor is recovered by the depressure vapor contacting the feed tank and heating up at least one stream forwarded into the feed tank.

The present disclosure provides processes and systems for heat integration in ethanol production. In one embodiment, a feed mixture is distilled with one or more distillation units to remove at least a portion of the water, and form a distillation unit bottom stream, a vaporous overhead stream, and a fusel oil stream. Molecular sieve units are regenerated by vacuum or a combination of vacuum and optionally a portion of the product stream to form one or more regenerate streams. A feed tank is configured to receive at least one selected from a condensed portion of the regenerate streams and a portion of a vaporous depressure stream, to form a feed stream. The energy contained in the depressure vapor is recovered by the depressure vapor contacting the feed tank and heating up at least one stream forwarded into the feed tank.

Suggested is a process for the production of solid cooling agents, wherein a pre-scraped melt, i.e., a melt of menthol compounds with added seed crystals is applied to a pre-cooled area by even deposition of drops.

Suggested is a process for the production of solid cooling agents, wherein a pre-scraped melt, i.e., a melt of menthol compounds with added seed crystals is applied to a pre-cooled area by even deposition of drops.

In one embodiment, a light emitting device includes a lighting element located in a housing, wherein the housing is formed from a plastic composition including, for example, a polycarbonate formed from reacting, in the presence of a transesterification catalyst, a diaryl carbonate ester and a bisphenol A, wherein the bisphenol A has a sulfur concentration of 1 ppm to 15 ppm, based upon a weight of the bisphenol A; and a conversion material wherein the conversion material includes an inorganic material that converts radiation of a certain wavelength and re-emits of a different wavelength; wherein after the conversion material has been exposed to an excitation source, the conversion material has a luminescence lifetime of less than 10.sup.−4 seconds when the excitation source is removed.

In one embodiment, a light emitting device includes a lighting element located in a housing, wherein the housing is formed from a plastic composition including, for example, a polycarbonate formed from reacting, in the presence of a transesterification catalyst, a diaryl carbonate ester and a bisphenol A, wherein the bisphenol A has a sulfur concentration of 1 ppm to 15 ppm, based upon a weight of the bisphenol A; and a conversion material wherein the conversion material includes an inorganic material that converts radiation of a certain wavelength and re-emits of a different wavelength; wherein after the conversion material has been exposed to an excitation source, the conversion material has a luminescence lifetime of less than 10.sup.−4 seconds when the excitation source is removed.

The present invention relates to a xylitol preparation device integrating evaporation, crystallization and centrifugation, including a xylitol tank, a cleaning liquid tank, a recycling tank and a multiple distribution system, wherein the multiple distribution system includes J groups of evaporators for evaporation concentration, K groups of vacuum crystallization kettles for vacuum crystallization and L groups of centrifuges for centrifugation, wherein 2≤J≤6, 6≤K≤12 and 2≤L≤4; the evaporator, the vacuum crystallization kettle and the centrifuge in different groups are sequentially connected in series with one another through a pipeline and a valve respectively; by controlling on and off of each valve, a xylitol exchange liquid is switched and controlled between a series-connection mode and a parallel-connection mode in the multiple distribution system to enable evaporation, crystallization and separation processes to reach an optimal effect distribution so as to improve productivity. The present invention further discloses a control method of the device. The processes and equipment of the present invention are highly integrated to realize continuous integrated production of xylitol preparation with low energy consumption and high automation degree, and full utilization of raw materials.