己二酸合成中高岭土对催化活性组分的载体作用

Loading performance of kaolin carrier for catalytically active component in synthesis of adipic acid

以高岭土为载体、钨粉为催化剂前驱物,过氧钨酸为催化剂活性组分,经催化H2O2-环己酮的反应合成了己二酸.利用反应过程中催化活性组分在高岭土表面的选择性吸附,在反应完成后分离出负载过氧钨酸的高岭土并重复循环使用,考察了反应条件对己二酸收率的影响,并测定了过氧钨酸-高岭土的重复使用性能.采用红外光谱分析了高岭土及循环使用的过氧钨酸-高岭土的化学结构.结果表明,载体高岭土能够在反应过程中有效负载过氧钨酸,并且过氧钨酸-高岭土第4次循环利用后其产物的收率基本不随重复利用次数增加而发生变化.

Adipic acid was synthesized via the reaction between H2O2 and cyclohexanone reactants in the presence of kaolin as the carrier, tungsten powder as the precursor of the catalyst, and peroxotungstic acid as the catalyst active component. Based on the selective adsorption of the catalyst active component on the surface of kaolin, kaolin-supported peroxotungstic acid was separated and reused in follow-up reactions. The effect of reaction condition on the yield of adipic acid was investigated, the recycling performance of the kaolin-supported peroxotungstic acid was evaluated, and the chemical structure of kaolin and reused kaolin-supported peroxotungstic acid was analyzed by infrared spectrometry. Results indicate that kaolin is able to well support peroxotungstic acid during the reaction. After kaolin-supported peroxotungstic acid is reused for four cycles, the yield of the target product remains nearly unchanged with further increase of the recycling number of kaolin-supported peroxotungstic acid.