Patent application number | Description | Published |
20080200734 | CRYSTALLIZATION PROCESSES FOR PRODUCING BISPHENOLS - Processes for producing bisphenols (e.g., bisphenol A (BPA)) having a purity greater than 99.7% are described, such processes including reacting a phenol and acetone in the presence of an acidic catalyst to form a product mixture comprising a bisphenol; removing at least a portion of the bisphenol from the product mixture in the form of a bisphenol/phenol adduct by crystallization, filtration and washing to provide bisphenol/phenol adduct crystals; and removing at least a portion of the phenol from the bisphenol/phenol adduct crystals to provide the bisphenol having a purity of more than 99.7%; wherein the crystallization comprises continuous suspension crystallization and is carried out in at least three crystallization devices arranged such that the product mixture is first cooled in a first stage of the crystallization to a temperature of 50 to 70° C. in a first crystallization device and a second crystallization device connected in parallel, and subsequently cooled in a second stage of the crystallization to a temperature of 40 to 50° C. in a third crystallization device connected downstream in series to the first and second crystallization devices, and wherein a total dwell time of the product mixture in the crystallization is more than 4 hours. | 08-21-2008 |
20080306174 | METHOD FOR DECANTING PRECONDITIONED ION-EXCHANGE RESIN SUSPENSIONS - A process for the storage or transportation of pretreated, conditioned ion exchangers as catalysts for chemical reactions is disclosed. The preconditioned ion-exchange resin is kept as preconditioned ion-exchange resin suspension in a storage or transporting container. The container with the preconditioned ion-exchange resin suspension is transported to either a storage site for storage or to a reactor for transfer of the resin to the reactor. | 12-11-2008 |
20090140215 | CATALYST FOR PRODUCING CARBON NANOTUBES BY MEANS OF THE DECOMPOSITION OF GASEOUS CARBON COMPOUNDS ON A HETEROGENEOUS CATALYST - The present invention relates to a process for the production of carbon nanotubes, in particular those having a diameter of 3-150 nm and an aspect ratio of length:diameter (L:D)>100, by decomposition of hydrocarbons on a heterogeneous catalyst which comprises Mn, Co, preferably also molybdenum, and an inert support material, and the catalyst and the carbon nanotubes themselves and the use thereof. | 06-04-2009 |
20100305365 | REGENERATION OF ACIDIC ION EXCHANGERS - The invention relates to a method for regenerating acidic cation exchangers, which are used as catalysts in the reaction of phenols with aldehydes or ketones to give bisphenols, in particular to give bisphenol A, with acids, with the proviso that, in the method according to the invention, these cation exchangers experience very little mechanical damage due to swelling processes during the regeneration process. | 12-02-2010 |
Patent application number | Description | Published |
20100305365 | REGENERATION OF ACIDIC ION EXCHANGERS - The invention relates to a method for regenerating acidic cation exchangers, which are used as catalysts in the reaction of phenols with aldehydes or ketones to give bisphenols, in particular to give bisphenol A, with acids, with the proviso that, in the method according to the invention, these cation exchangers experience very little mechanical damage due to swelling processes during the regeneration process. | 12-02-2010 |
20110224357 | CARBON NANOTUBES AND ORGANIC MEDIA CONTAINING MICROGELS - The invention relates to a composition containing at least one microgel, at least one carbon nanotube and at least one organic medium. Said organic medium can be cross-linked or non cross-linked. | 09-15-2011 |
20110251309 | BRANCHED MELT POLYCARBONATE WITH LOW CONTENT OF DEFECTIVE STRUCTURES - The present invention relates to an aromatic branched polycarbonate, produced via melt transesterification of a bisphenol with a diaryl carbonate in the presence of a branching agent, wherein the aromatic branched polycarbonate comprises branching point structures and structures of formula (D) | 10-13-2011 |
20110251438 | PURIFICATION OF TRIS-HYDROXYARYL COMPOUNDS - The present invention is directed to a composition comprising a tris-hydroxyaryl compound having a metal ion impurity content of less than 10 ppm and to a process for the purification of tris-hydroxyaryl compound having a metal ion impurity, comprising at least the following steps:
| 10-13-2011 |
20120010433 | DEVICE AND PROCESS FOR SOLID/LIQUID SEPARATION OF SOLID-LIQUID SUSPENSIONS - In a device and a process for continuous solid/liquid separation (filtration) of solid-liquid suspensions on moving filters, for example on rotating drum filters or belt filters, the active filtering layer contains a woven fabric material composed of synthetic fibres, which has an enhanced filtrate permeability and also an enhanced thermal stability with improved dimensional stability, and also improved mechanical strength compared with polypropylene fibres. | 01-12-2012 |