己二酸合成中催化剂重复使用稳定性研究

Study of Stability of Catalyst Reuse in Green Synthesis of Adipic Acid

以 Na_2WO_4为催化剂前驱体,原位制备了均相钨催化剂,并用于 H_2O_2氧化环己烯制备己二酸的反应。主要考察了反应条件和催化剂母液处理条件对催化剂重复使用稳定性的影响。结果表明,催化剂溶液在50℃下进行浓缩处理,浓缩倍数为1.875,采用适当的 H_2O_2加入方式,并在反应回流结束后控制适当的反应温度和反应时间,可以获得较好的催化反应稳定性。

The stability of catalyst reuse in green synthesis of adipic acid via directly oxidation of cyclohexene with 30% H2O2 in homogenous tungsten system without organic solvent, ligand and phase-transfer agents was investigated. The influence of temperature and time after reflux, the concentrating conditions of catalyst solution and addition methods of H2O2 on the yield of adipic acid and stability of the catalyst were studied. Meanwhile, the structural change of tungsten catalyst was analyzed. The experimental results indicated that the optimal reaction condition of the cycle reaction was at 90℃, reacting 6 h, concentrated temperature 50 ℃, concentrated factor 1. 875. The catalyst could be reused 6 times and the adipic acid yield exceeded 70% under these conditions.