MOF-74负载磷钨酸催化剂的制备及其催化环己烯氧化制己二酸性能

以Cu²⁺为金属中心、2,5-二羟基对苯二甲酸为有机配体、磷钨酸(H₃PW₁₂O₄₀,简称PTA)为活性组分，采用热溶剂法一步原位合成PTA负载量(w)为x%的一系列PTA/Cu-MOF-74催化剂(x%PTA@Cu-MOF-74,x=0,10,20,30,40)。采用傅里叶变换红外光谱、X射线衍射、扫描电镜和氮气吸附-脱附等表征手段对制得催化剂进行系统分析，同时对其催化环己烯氧化合成己二酸的活性进行测试。结果表明：PTA活性组分成功负载到Cu-MOF-74骨架中，并且MOF-74的骨架结构保持完整；在反应温度为80℃、反应时间为6 h、环己烯进料量为1 mL、双氧水(H₂O₂质量分数30%)进料量为4.5 mL、10%PTA@Cu-MOF-74催化剂用量为0.2 g的反应条件下，己二酸的产率最佳，为61.96%;相同试验条件下上述催化剂重复使用4次后，己二酸的产率仍达59.89%,与使用新鲜催化剂时相比降低幅度仅为3.3%。

PREPARATION OF MOF-74 SUPPORTED PHOSPHOTUNGSTIC ACID CATALYST AND ITS CATALYTIC PERFORMANCE FOR OXIDATION OF CYCLOHEXENE TO ADIPIC ACID

With Cu²⁺ as the metal center, 2,5-dihydroxyterephthalic acid as the organic ligand and phosphotungstic acid (H₃PW₁₂O₄₀, PTA for short) as the active component, a series of PTA/Cu-MOF-74 catalysts (x%PTA@Cu-MOF-74, x=0, 10, 20, 30, 40）with x% PTA loading (w) were synthesized by one-step hot solvent method. The catalysts were characterized by Fourier transform infrared spectroscopy, powder X-ray diffraction, scanning electron microscopy, nitrogen adsorption-desorption, and the catalytic activity of cyclohexene oxidation to adipic acid was tested. The results showed that the active component of PTA was successfully loaded into the Cu-MOF-74 skeleton, and the skeleton structure of MOF-74 remained intact. Under the reaction temperature of 80 ℃, reaction time of 6 h, the volume of cyclohexene of 1 mL, the volume of 30% H₂O₂ of 4.5 mL, and the dosage of 10%PTA@Cu-MOF-74 catalyst of 0.2 g, the yield of adipic acid was the best (61.96%), and the yield of adipic acid was 59.89% after the catalyst was reused for 4 times under the same test conditions, which was only 3.3% lower than that of using fresh catalyst.