摘要:
Aromatic carboxylic acids are produced by oxidation of the corresponding aryl alkyl ketones with molecular oxygen in the presence of a catalyst comprising a manganese salt. The oxidation takes place under mild conditions and the starting materials are easily accessible.
摘要:
Es wird ein Reaktor (1) mit einem Kontaktrohrbündel (2) vorgeschlagen, durch dessen die Kontaktrohre umgebenden Raum ein Wärmetauschmittelkreislauf geleitet wird, mit Ringleitungen (3, 4) an beiden Reaktorenden mit Mantelöffnungen (5, 6) für die Zu- bzw. Abführung eines Wärmetauschmittels mittels einer Pumpe über einen aussenliegenden Wärmetauscher, wobei das Wärmetauschmittel der unteren Ringleitung (4) zugeführt und über die obere Ringleitung (3) zum Wärmetauscher abgeführt wird, sowie mit Umlenkscheiben (7), die abwechselnd in der Reaktormitte und am Reaktorrand einen Durchtrittsquerschnitt freilassen. Dabei sind die obere (3) und untere (4) Ringleitung jeweils mittels einer zylindermantelförmigen Zwischenwand (8, 9) in eine innere (11, 13) und eine äussere (12, 14) Ringleitung geteilt, und das wärmetauschmittel wird der äusseren unteren Ringleitung (14) über einen Bereich ausserhalb des Reaktors der inneren oberen Ringleitung (11), über deren Mantelöffnungen (5) dem die Kontaktrohre (2) umgebenden Raum, über die Mantelöffnungen (6) der inneren unteren Ringleitung (13) und anschliessend über einen Bereich ausserhalb des Reaktors der äusseren oberen Ringleitung (12) zugeführt.
摘要:
Processes for preparing aromatic carboxylic acids. Cinnamaldehyde is hydrogenated to produce a mixture of hydrogenation products, namely hydrocinnamaldehyde and hydrocinnamic alcohol. The mixture is then oxidized using a suitable oxidizing agent to substantially completely convert both hydrocinnamaldehyde and hydrocinnamic alcohol to hydrocinnamic acid.
摘要:
Methods of producing terephthalic acid are described. The methods involve using a substantially pure p-toluic acid stream. The substantially pure p-toluic acid stream, a solvent comprising an ionic liquid and optionally a carboxylic acid, a bromine source, a catalyst, and an oxidizing agent are contacted to produce a product comprising terephthalic acid.
摘要:
A low temperature process for preparing an aromatic acid having formula (I), said process comprising reacting an aromatic aldehyde having formula (II) with a gas having an oxygen content of 1 to 100 weight percent, based on the total weight of the gas, at a temperature of about 20 °C to less than 100 °C in the presence of the supported Group VIII metal catalyst, and a solvent having a flash point greater than 95 °C and/or a melting point less than 55 °C, provided that the flash point of the solvent is greater than the reaction temperature, wherein R and R are independently selected from the group consisting of hydrogen and a C1-C8 linear, branched or cyclic alkyl group. The process of the invention yields an aromatic acid in excellent yield, and (i) does not involve the use of deleterious oxidizing agents; (ii) is essentially free of by-products; and (iii) is accomplished at a temperature of less than 100 °C.
摘要:
Disclosed is a process for manufacturing an aromatic diacid in one step with a single catalyst system which comprises: a) introducing into a reactor an aromatic hydrocarbon containing the number of rings desired in the product diacid with one or more alkyl groups attached to the rings; b) reacting said aromatic hydrocarbon in the presence of an oxidant supply and a single catalyst system comprising at least one catalyst selected from Group IB, IIB, VB, or VIIB of the Periodic Table, in a reaction medium capable of stabilizing the aromatic acids formed against further oxidation to water and CO2, or decarboxylation to aromatic hydrocarbons, and also capable of allowing the isomerization of the acids so formed to the desired diacids; and c) reacting said hydrocarbon feed with said oxidant in the presence of said catalyst system until a desired amount of said feed is oxidized to carboxylic acids and isomerized to the desired diacid product.
摘要:
The invention relates to a method for producing acid phthalic anhydride by catalytic gas phase oxidation of o-xylol or naphthalene or o-xylol/naphthalene mixtures with a molecular gas containing oxygen on a shell catalyst consisting of an inert, non-porous carrier material to which a coating of a catalytically active mass containing titanium dioxide and vanadium pentoxide is applied, wherein a catalyst is used whose catalytically active mass consists of 3 to 6 wt. % of vanadium pentoxide calculated as V2O5, 0.3 to 0.5 wt. % of a cesium compound calculated as Cs, and the remainder up to 100 wt. % of titanium dioxide anastase modification, in the presence or absence of a catalyst in the form of a shell differing from the above-mentioned catalyst which is used to produce gas-phase oxidation of o-xylol or naphthalene or o-xylol/naphthalene mixtures. In the presence of a second catalyst of this type, said catalyst is introduced to the reactor with the catalyst of the above-mentioned composition in a combined charge.
摘要翻译:一种用于通过邻二甲苯或萘或邻二甲苯/萘混合物的催化气相氧化用含分子氧在涂层催化剂的催化活性,其包括含有二氧化钛和五氧化钒上的惰性,无孔载体材料的气体制备邻苯二甲酸酐的过程 质量被沉积以层的形式,其中一个其催化活性组合物包含3至6重量五氧化二钒,作为V 2 O 5计算的%,0.3至0.5重量铯化合物,以Cs计算的%,和催化剂 余量至100重量锐钛矿改性的二氧化钛,在存在或不存在的%,使用这种不同的经涂覆的催化剂的邻二甲苯或萘或邻二甲苯/萘混合物的催化气相氧化和第二中的这种存在的一个 催化剂本站立在复合床与所述催化剂组合物上方 使用反应器中。
摘要:
A method for digestion of a crude terephthalic slurry obtained from oxidation of para- xylene in a bubble column reactor oxidation process is provided. The method is conducted in one or more bubble column reactors having one or more segregrated zones defined by horizontal baffles and particle flow through the digestion system is controlled to maximize conversion of partial oxidation intermediates to terephthalic acid while minimizing formation of other contaminant products. Temperature, oxygen flow and content as well as other process and equipment variables are controlled throughout the process to support formation of terephthalic acid. Also provided are bubble column digestion systems stnictured to conduct the digestion method.