Patent application number | Description | Published |
20090143601 | METHOD FOR PREVENTING FUMARIC ACID DEPOSITS IN THE PRODUCTION OF MALEIC ACID ANHYDRIDE - The present invention provides a process for preventing fumaric acid deposits in the preparation of maleic anhydride, comprising the following steps: | 06-04-2009 |
20100069681 | PROCESS FOR PREPARING 3-ALKOXYPROPAN-1-OLS - The present invention relates to a process for preparing 3-alkoxypropan-1-ols of the general formula I | 03-18-2010 |
20110021789 | PROCESS FOR SEPARATING OFF FUMARIC ACID AND OTHER MINOR COMPONENTS DURING THE PRODUCTION OF MALEIC ANHYDRIDE - A process for decreasing fumaric acid deposits in the preparation of maleic anhydride by heterogeneously catalyzed oxidation of a hydrocarbon with molecular oxygen, in which the maleic anhydride is absorbed from the crude product mixture in an absorbent in an absorption column and desorbed again in a desorption column, the entirety or a portion of the absorbent depleted in maleic anhydride, for controlled precipitation of fumaric acid, being cooled and/or concentrated by evaporating a portion of the absorbent to such an extent that the difference between the concentration of fumaric acid in the recycle stream at the outlet of the desorption column under the conditions existing there and the equilibrium concentration of fumaric acid according to the solubility curve after the cooling and/or evaporation of a portion of the absorbent is greater than or equal to 250 ppm by weight, and the fumaric acid precipitated as a solid is removed completely or partly from the absorbent recycling system and the fumaric acid-depleted absorbent is recycled completely or partly to the absorption column. | 01-27-2011 |
20110245517 | PROCESS FOR PREPARING TETRAHYDROFURAN - The present invention relates to a process for preparing tetrahydrofuran by absorption of C | 10-06-2011 |
20110257426 | PROCESS FOR PREPARING CARBOXYLIC ESTERS BY REACTIVE DISTILLATION - In a process for preparing carboxylic esters by transesterification, a first feed stream comprising a first carboxylic ester, e.g. methyl formate, is introduced laterally into a reaction column at least one first feed point located between top and bottom of the reaction column and a second feed stream comprising a first alcohol, e.g. ethanol, is introduced laterally into the reaction column at a second feed point located above the first feed point and are reacted in a reaction zone of the reaction column to form a second carboxylic ester and a second alcohol. The first alcohol has a higher molecular weight than the second alcohol. A product fraction comprising the second carboxylic ester and unreacted first carboxylic ester is taken off at an offtake point located above the second feed point. At the bottom of the reaction column, a bottom fraction comprising the second alcohol and unreacted first alcohol is taken off. The product fraction is separated by distillation at a pressure which is different from the pressure in the reaction column into second carboxylic ester and a fraction comprising unreacted first carboxylic ester and the fraction comprising unreacted first carboxylic ester is at least partly recirculated to the reaction zone. | 10-20-2011 |
20110257427 | PURIFICATION OF CARBOXYLIC ESTERS BY EXTRACTIVE DISTILLATION - In a process for purifying carboxylic esters such as ethyl formate, a carboxylic ester to be purified is distilled in the presence of an extractant, preferably by (a) allowing vapor of the carboxylic ester to be purified to ascend in a distillation column; (b) conveying the extractant in countercurrent to the vapor in an extractive distillation column; (c) taking off pure carboxylic ester above the extractive distillation zone. The extractant is, for example, selected from among diols, polyols, open-chain or cyclic amides. | 10-20-2011 |
20120010431 | METHOD FOR PRODUCING 1-ADAMANTYL TRIMETHYLAMMONIUM HYDROXIDE - The present invention relates to a process for preparing 1-adamantyltrimethyl-ammonium hydroxide. | 01-12-2012 |
20140171709 | REACTOR FOR CARRYING OUT AN AUTOTHERMAL GAS-PHASE DEHYDROGENATION - A reactor for gas-phase dehydrogenation of a hydrocarbon-comprising stream with an oxygen-comprising stream over a monolithic heterogeneous catalyst. Catalytically active zone(s) comprising monoliths packed next to one another and/or above one another and a mixing zone having fixed internals upstream of each catalytically active zone. Feed line(s) for the hydrocarbon-comprising gas stream to be dehydrogenated at the lower end of the reactor. Independently regulable feed line(s), which supply distributor(s), for the oxygen-comprising gas stream into each of the mixing zones and discharge line(s) for the reaction gas mixture of the autothermal gas-phase dehydrogenation at the upper end of the reactor. The interior wall of the reactor is provided with insulation. The catalytically active zone(s) is accessible from the outside of the reactor via manhole(s). The catalytically active zone(s), mixing zone, independently regulable feed line(s), and distributor(s), may be designed as one component which can individually be mounted and removed. | 06-19-2014 |