4659-50-1Relevant academic research and scientific papers
PROCESS FOR PRODUCING AROMATIC POLYCARBOXYLIC ACID
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Page/Page column 14-15, (2011/04/18)
A process for producing an aromatic polycarboxylic acid in which all alkyl groups are converted into carboxyl groups in a high yield by decreasing a residual amount of an intermediate product is provided. The process comprises oxygen-oxidizing an aromatic compound having a plurality of alkyl groups (e.g., durene) in the presence of a catalyst containing a cyclic imino unit having an N—OR group (wherein R represents a hydrogen atom or a protecting group for a hydroxyl group) and a transition metal co-catalyst (e.g., a cobalt compound, a manganese compound, and a zirconium compound) under heating in a lower-temperature zone and a higher-temperature zone to produce an aromatic polycarboxylic acid in which a plurality of alkyl groups are oxidized into carboxyl groups. In an initial stage of the reaction, the reaction may be conducted in a first lower-temperature zone (a reaction temperature of 60 to 120° C. and a second lower-temperature zone (an intermediate temperature zone) (a reaction temperature of 100 to 140° C.); and then, in a latter stage of the reaction, the reaction may be conducted in a higher-temperature zone (a reaction temperature of 110 to 150° C.).
