一种新型合成碳酸二苯酯的钯(Ⅱ)-1,2-环己二胺配合物固载型催化剂研究

A Novel Palladium(Ⅱ)-1,2-Cyclohexanediamine Complex Loaded Catalyst for Synthesis of Diphenyl Carbonate

摘要:

采用椰壳活性炭为载体, 通过20% HNO3氧化处理, 在载体表面生成了0.383 mmol/g酚羟基, 之后成功与N,N’-二[(三甲氧基硅)丙基]-1,2-环己二胺反应, 引入了1,2-环己二胺有机氮双齿配体用于络合钯离子, ICP结果表明钯离子的固载量为0.79%。以FT-IR, XPS及N2吸附-脱附等手段表征了催化剂制备过程中的各种中间体。在高压反应釜中以苯酚氧化羰基化法催化合成碳酸二苯酯(DPC), 确定了最佳工艺条件为反应温度100 ℃、反应压力7.0 Mpa、反应时间5 h及二氯甲烷为溶剂, 并在最佳工艺条件下测得产物DPC的收率为7.43%。

Abstract:

Coconut shell activated carbon (AC) was used as carrier to covalently immobilize Pd2 complex. The content of hydroxyl groups on the carbon surface was increased to 0.383 mmol/g after 20% HNO3 oxidation. Nitrogen-containing bidentate ligand was synthesized by grafting the oxidized AC with N,N’-bis[(triethoxysilyl)propyl]-1,2-cyclohexanediamine, followed by Pd2 complexation. The ICP result shows that the Pd2 loading capacity reached 0.79%. The samples were characterized by FT-IR, XPS and N2 adsorption-desorption. Diphenyl carbonate (DPC) was synthesized in a high pressure reaction vessel by oxidative carbonylation of phenol over the AC loaded Pd2 complex catalyst. The optimum operation conditions were determined as follows: reaction temperature of 100 ℃, reaction pressure of 7.0 MPa, reaction time of 5 h, and CH2Cl2 was used as solvent. The DPC yield reached 7.43% under the above conditions.