采用椰壳活性炭为载体,通过20%HNO3氧化处理,Boehm滴定表明活性炭表面羟基含量达0.376 mmol/g.之后分别接枝(MeO)3Si(CH2)3NH2和(MeO)3Si(CH2)3Cl,并成功合成了两种不同类型的含氮双齿配体用来配合钯离子,以FT-IR、XPS、1H NMR、ICP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反应考察了所制催化剂的催化性能.结果表明,在100℃,7.0 MPa及p(CO)/p(O2)=10/1下,二氯甲烷为溶剂,以环庚二胺配体配合的钯离子为催化剂,苯酚转化率及产物碳酸二苯酯(DPC)选择性分别为11.91%、86.82%,对于双氰基配体配合的催化剂,苯酚转化率及产物DPC选择性分别为6.22%及81.02%.
Coconut shell activated carbon (AC) was used as carrier to covalently immobilize Pd2+ complexes. Boe- hm titration showed that hydroxyl content of the carbon surface reached O. 376 mmol/g after 20% HNO3 oxidation treatment. Two types of nitrogen-containing bidentate ligands were subsequently synthesized by grafting the oxidized AC with (MeO) 3Si ( CH2 ) 3NH2 or (MeO) 3Si ( CH2 ) 3C1. The samples were characterized by FT-IR, XPS, I H NMR, ICP and N2 adsorption-desorption. CH2C12 was used as solvent, oxidation carbonylation of phenol was inves- tigated in a high pressure reaction vessel at 100 ℃, 7.0 MPa and p( CO)/p( 02) = 10/1 over the immobilized Pd2+ complexes. The results show that the conversion of phenol was 11.91%, and the diphenyl carbonate (DPC) selectivity was 86.82% for the cycloheptyl diamine ligand-complexed ligand-complexed ones displayed a phenol conversion of 6.22% and palladium ions. Comparatively, the bisnitrile a DPC selectivity of 81.02%