Pd催化水溶液中三氯新的加氢脱氯

Pd-catalyzed Hydrodechlorination of Triclosan in Aqueous Solutions

以10mgw(Pd)=5%的Pd/C为催化剂,在35℃和1 01×105Pa下,ρ(三氯新)=4g/L的三氯新水/乙醇〔V(水)∶V(乙醇)=1∶1〕溶液20mL反应30min就100%脱氯。在乙醇中,三氯新加氢1h氯的去除率为68%。水的存在,改善了三氯新的反应环境,消除了NaCl在催化剂上的富集,使催化剂保持了较高的活性。在水溶液中,ρ(氯化物)=5g/L的碱金属或碱土金属氯化物的存在,对三氯新的加氢脱氯反应没有影响,这是因为这些无机氯化物在水中完全电离,离子化的无机氯化物不会堵塞反应孔道,也不会在催化剂表面吸附,因此不会阻碍三氯新的加氢脱氯。

Triclosan was completely hydrodechlorinated in H_2O/ethanol solutions in 30 min over 10 mg w(Pd)=5% Pd/C at 35 ℃ and 1.01×10~5 Pa.However,only 68% triclosan was hydrodechlorinated in ethanol.In contrast to the dechlorination in ethanol,the catalyst showed higher activity in H_2O/ethanol.The presence of H_2O improved the reaction environments and eliminated the adsorption and accumulation of NaCl on the surface of the catalyst.Due to no adsorption or accumulation on the surface of the catalyst,the presences of alkali metal or alkali earth metal chlorides in aqueous solutions had no influence on the dechlorination of triclosan and the activity of the catalyst.