连接链长度对交联聚苯乙烯固定N-羟基邻苯二甲酰亚胺催化环己基苯氧化的影响

为解决N-羟基邻苯二甲酰亚胺(NHPI)催化剂难以回收利用的问题，采用不同链长的卤代烃，通过烷基化反应，将NHPI化学固定于交联聚苯乙烯(CPS)微球，制得了具有不同长度连接链的CPS-NHPI-C_n非均相催化剂。采用X射线光电子能谱(XPS)、红外光谱(FT-IR)、N₂吸附-脱附(BET)、扫描电子显微镜(SEM)等分析手段进行表征。将所制备的CPS-NHPI-C_n用于催化环己基苯(CHB)氧化过程，考察了连接链长度(C₁~C₉)及反应条件对催化性能的影响。结果表明：连接链长度明显影响CPS-NHPI-C_n的催化性能，连接链长从度C₁增至C₆，CPS-NHPI-C_n催化剂的活性增加。以CPS-NHP-C₆为催化剂，在95 ℃、1 MPaO₂分压下反应8h，环己基苯的转化率为28.4%，环己酮和苯酚的选择性分别为90.7%和87.6%。CPS-NHP-C6循环使用10次，其催化性能没有明显下降。

Effects of Link Chain Length on Oxidation of Cyclohexylbenzene Catalyzed by immobilized N-Hydroxyphthalimide on Cross-linked Polystyrene

To solve the drawbacks of difficult recovery and reuse of N-hydroxyphthalmide (NHPI), the cross-linked polystyrene (CPS) immobilized NHPI (CPS-NHPI-C_n) catalysts with different link chain lengths were prepared by chemical immobilization of NHPI on the surface of CPS microsphere using different chain lengths of halogenated hydrocarbons as alkylation agents. The synthesized CPS-NHPI-C_n catalysts were characterized by XPS, FT-IR, BET and SEM, and evaluated by cyclohexylbenzene oxidation. The effects of link chain length (C₁-C₉) in CPS-NHPI-C_n and reaction conditions on the catalytic performance were investigated. Results indicate that the link chain length affects the catalytic performance of CPS-NHPI-C_n obviously, and the catalytic activity increases with the link chain number from 1 to 6. Using CPS-NHPI-C₆ as catalyst, at 95 ℃ and 1 MPaO₂ partial pressure for 8 h, the cyclohexylbenzene conversion is 28.4%, with the selectivity of cyclohexanone and phenol is 90.7% and 87.6%, respectively. After the CPS-NHPI-C6 catalyst has been reused for 10 times, the catalytic performance is still as high as that of fresh one.