Abstract: Granular activated carbon(GAC) stabilized Pd/Fe nanoparticles were prepared by using ultrasound-assisted liquid phase reductive method. The influence factors and degradation kinetics of 2-chlorobiphenyl(2-CB) catalytic reductive dechlorination by GAC stabilized Pd/Fe nanoparticles were explored. The experimental results showed that the diameters and specific surface areas of most particles prepared under 40kHz and 150W ultrasound were obviously modified. The diameters of most particles were less than 100nm and the specific surface areas were increased by 21.73%. Up to 95% of 2-CB was removed in 300min with mass fraction of Pd in GAC stabilized Pd/Fe nanoparticles of 0.3%,initial 2-CB concentration of 5mg/L,GAC dosage of 0.15g/L, Pd/Fe nanoparticles of 5.0g/L, initial pH=3.0,and reaction temperature of 25℃. The degradation of 2-CB followed pseudo-first-order kinetics reaction and the apparent pseudo-first-order kinetics constant was 3.88×10^-2min^-1.

Key words: ultrasound, granular activated carbon(GAC), Pd/Fe nanoparticles, 2-chlorobiphenyl, catalysis, reduction, kinetics

摘要： 利用超声波强化液相还原法制备活性炭颗粒（GAC）稳定化纳米级Pd/Fe复合颗粒，并对2-氯联苯（2-CB）进行催化还原脱氯研究。结果表明：40kHz超声波辐照强化下制备的GAC稳定化纳米级Pd/Fe复合颗粒的比表面积、粒径和分散性均较普通液相还原法制备的复合颗粒有明显改善，粒径均在100nm以下，比表面积增大了21.73%。当复合颗粒钯化率为0.3%（质量分数）且GAC和Pd/Fe投加量分别为0.15g/L和5.0g/L时，在反应温度25℃、初始pH为3的条件下反应300min后，对初始质量浓度为10mg/L的2-CB降解率近95%，符合拟一级反应动力学，反应速率常数为3.88×10^-2min^-1。

关键词: 超声波, 活性炭颗粒, 纳米级Pd/Fe颗粒, 2-氯联苯, 催化, 还原, 动力学