摘要:
The present invention relates to a continuous process for purifying a dialkyl carbonate/alkyl alcohol mixture in the preparation of dialkyl carbonate by catalysed transesterification of a cyclic alkylene carbonate (e.g. ethylene carbonate or propylene carbonate) with alkyl alcohols. For the increase in the product quality of the dialkyl carbonate, the selection of the operating parameters of the dialkyl carbonate purification column are crucial, in order to reduce the formation of unwanted by-products such as alkoxy alcohols and aliphatic carbonate ethers.
摘要:
Silane is produced in a continuous process by disproportionating trichlorsilane in at least 2 recreation areas for reaction/distillation, which are run through by a countercurrent of steam and liquid in the presence of catalytically active solid under a pressure which ranges between 500 mbar and 50 bar.
摘要:
The present invention relates to a process for the production of bis(4-hydroxyaryl)alkanes by an acid-catalyzed reaction between aromatic hydroxy compounds and ketones, in which the temperature, ketone content and water content of a liquid reaction mixture are adjusted by means of a suitably composed gas phase.
摘要:
The present invention relates to a continuous process for preparing lower dialkyl carbonates as main product and alkylene glycol as by-product by transesterification of a cyclic alkylene carbonate (e.g. ethylene carbonate or propylene carbonate) with lower alkyl alcohols in the presence of a catalyst and also the required purification of the dialkyl carbonate in a subsequent process step. To optimize the economics and energy efficiency of the process, additional devices are used for intermediate heating of the liquid streams in the apparatus.
摘要:
The present invention relates to a process for heterogeneously catalyzed partial esterification of (meth)acrylic acid with oxyalkylated polyols, wherein the oxyalkylated polyols have at least 3 free hydroxyl groups, and wherein the catalyst is selected from the group comprising acidic ion exchange resins and/or acidic zeolites. The invention further relates to (meth)acrylic esters and urethane acrylates, obtained by a process according to the present invention, and to the use thereof as radiation-curable compounds.
摘要:
The present invention relates to a continuous isothermal process for preparing mononitrotoluenes in the presence of a mixed acid component comprising mixtures of sulfuric acid and phosphoric acid with concentration of the resultant waste acid and recycling of the concentrated waste acid to the process.
摘要:
Method of dispensing moist, sticky or statically charged bulk material into a fluid pervious container having an opening for receiving said bulk material, which comprises conveying a bulk material, as a suspension or dispersion in a fluid, from a reservoir, and introducing said suspension or dispersion into the fluid-pervious container through said opening in the container to pass the fluid component of the suspension or dispersion through and out of the fluid-pervious container while the retaining the bulk material within the container, and recirculating the fluid to the reservoir.
摘要:
The present invention relates to a process for the continuous isothermal preparation of mononitrotoluenes with concentration of the resultant waste sulfuric acid and recycling of the concentrated waste sulfuric acid to the process.
摘要:
A contaminated carrier liquid in a chamber is cleaned by adding thereto oil particles having a charge and a composition that induces the formation of an hydroxide floc to form an intermediate filtering layer in the chamber. A top clean oil layer is recovered and a bottom clean aqueous layer is recovered. The intermediate layer can be treated to form a composition that can be recycled to form an hydroxide floc.
摘要:
The present invention relates to a continuous process for preparing lower dialkyl carbonates as main product and alkylene glycol as by-product by transesterification of a cyclic alkylene carbonate (e.g. ethylene carbonate or propylene carbonate) with lower alkyl alcohols in the presence of a catalyst and also the required purification of the dialkyl carbonate in a subsequent process step. To optimize the economics and energy efficiency of the process, additional devices are used for intermediate heating of the liquid streams in the apparatus.