摘要:
Settling times of a catalyst in the epoxidation of a cyclic, at least monounsaturated alkene are improved by a method, comprising epoxidizing a cyclic, at least monounsaturated alkene having from 8 to 20 carbon atoms in the ring in a reaction medium containing an oxidant and a catalyst system comprising at least one metal of Groups 4, 5 and 6 of the Periodic Table of the Elements, phosphoric acid and a phase transfer catalyst and a cyclic alkane having from 8 to 20 carbon atoms in the ring, which corresponds to the alkene reactant, as settling accelerator in the epoxidation reaction.
摘要:
The present invention relates to a process for the coammoximation, that is to say for the simultaneous ammoximation, of ketones, in particular of cyclic ketones such as cyclododecanone and cyclohexanone. Ammoximation is taken to mean here the preparation of oximes from ketones or aldehydes together with hydrogen peroxide and ammonia and in the presence of a catalyst which essentially consists of silicon, titanium and oxygen, for example titanium silicalite.
摘要:
A process for preparing cyclododecene by selective gas-phase hydrogenation of at least one starting material selected from cyclododecatriene, cyclododecadiene and mixtures thereof, wherein the starting material present in the gas phase is hydrogenated in the presence of a catalyst in a fixed-bed reactor and the Bodenstein number for the process is greater than 100.
摘要:
The invention relates to a method for the coammoxidation, i.e. for the simultaneous ammoxidation of ketones, especially of cyclic ketones such as cyclododecanone and cyclohexanone. The ammoxidatian method of the invention relates to the production of oximes from ketones or aldehydes using hydrogen peroxide and amnmonia and further using a catalyst that substantially consists of silicon, titanium and oxygen, such as for example titanium silicalite.
摘要:
Cyclic alcohols and ketones having from 7-16 carbon atoms are prepared by a process comprising oxidizing cycloalkanes having 7-16 carbon atom s in the presence of an oxygen-containing gas and a sparingly water-soluble and sparingly aliphatic or cycloaliphatic hydrocarbon-soluble transition metal catalyst of Group 6 to Group 12 combined with a boron compound, and separating the sparingly soluble transition metal catalyst by mechanical separation after completion of the reaction.
摘要:
A process for purifying laurolactam by means of integrated connection of distillation and crystallization is provided. The crystallization is performed as a solution or melt crystallization. The process reduces thermal stress applied to the laurolactam stream and improved yields are obtained. Raw materials are recovered and recycled in the production sequence.
摘要:
A process for purifying laurolactam by means of integrated connection of distillation and crystallization is provided. The crystallization is performed as a solution or melt crystallization. The process reduces thermal stress applied to the laurolactam stream and improved yields are obtained. Raw materials are recovered and recycled in the production sequence.
摘要:
The present invention provides a method for purifying laurolactam from a crude lactam mixture. In the method of the present invention, laurolactam is selectively crystallized by melt crystallization with controlled cooling of the crude lactam mixture.
摘要:
A process for oxidizing a cycloalkane, includes contacting a gas with a starting mixture, to form a product mixture, where the starting mixture contains (i) a cycloalkane, (ii) boric acid, and (iii) cobalt. The gas contains oxygen, the cycloalkane has 9 to 16 carbon atoms, and the product mixture contains a cyclic alcohol. The reactor output is increased by adding the cobalt salt, so that it is possible to lower the temperature, which decreases the rate of parallel and secondary reactions.
摘要:
Polyolefinic foam beads which can be processed over a wide temperature range to give molded articles where a ratio of the areas of low-temperature peak and high-temperature peak in the DSC curve during the first heating has a value of not more than 3, and where the heat of fusion of the secondary crystals is greater than 10 J/g.