纳米级Ni/Fe颗粒降解四氯化碳批实验研究

本文阐述了实验室合成纳米Fe和Ni／Fe双金属(直径为1-100hm)的有效方法，BET方法测得其比表面积为52．61m^2／g。并用制得的纳米颗粒对四氯化碳(CT)进行还原性脱氯的批实验，结果表明与微米级铁相比，纳米颗粒在固液比(0．4g／50mL)相对较低的条件下，对cT有明显的脱氯作用。反应进行1h，纳米Ni／Fe，纳米Fe和铸铁屑的脱氯率分别为98％，84％和65％；纳米Ni／Fe和纳米Fe产生的中间产物三氯甲烷(TCM)最大量分别为25％和59％，随之TCM又逐渐下降，尤其是纳米Ni／Fe在很短时间内，将TCM快速完全脱氯且产生27％甲烷CH4)和15％二氯甲烷(DCM)，并对DCM没有明显的脱氯作用。由于催化剂Ni的存在，大大降低了反应活化能，加快了脱氯速率，更重要的是，降低了反应副产物产量。

STUDY ON THE DEGRADATION OF CARBON TETRACHLORIDE USING NANOSCALE IRON PARTILCES

In this paper, an efficient method synthesizing nanoscale (l-100nm) iron and nickelized iron was presented. BET specific surface area of the synthesized metal particles was 52.61 m2/g. Nanoscale iron and nanoscale Ni/Fe bimetal were used to dechlorinate carbon tetrachloride (CT). Batch studies demonstrated that nanoscale particles can quickly and completely dechlorinate CT. When the reactions last 1 hour, the dechlorination rate was 98% for nanoscale Ni/Fe and 84% for nanoscale iron while 65% for cast iron particles. TCM emerged very quickly and peaked (25% for nanoscale Ni/Fe and 59% for nanoscale iron, respectively) around 1 hour corresponding to the disappearance of CT. Nanoscale particles enhanced dechlorination rate significantly,especially for nanoscale Ni/Fe bimetallic system. Complete reduction of TCM was observed around 4 hours. DCM (15%) and CH 4 (27%) accumulated steadily. Nanoscale particles were invaid for DCM. The presence of Ni as catalyst reduces activation energy and increases the rate of dechlorination reactions, more importantly, curtails production of chlorinated byproducts.