Liu Xitao, Yu Gang, Han Wenya
Persistent Organic Pollutants Research Centre, Department of Environmental Science and Engineering, Tsinghua University, Beijing 100084, China.
J Hazard Mater. 2007 Aug 25;147(3):746-51. doi: 10.1016/j.jhazmat.2007.01.076. Epub 2007 Jan 26.
The treatment of 2,4,5-trichlorobiphenyl (PCB29) in simulated soil-washing solution by granular activated carbon (GAC) adsorption and microwave (MW) regeneration was investigated in this study. The PCB29 adsorption process was carried out in a continuous flow adsorption column. After adsorption, the PCB29-loaded GAC was dried at 103 degrees C, and regenerated in a quartz reactor by 2450MHz MW irradiation at 700W for 5min. The efficacy of this procedure was analyzed by determining the rates and amounts of PCB29 adsorbed in successive adsorption/MW regeneration cycles. Effects of the regeneration on the textural properties and the PCB29 adsorption capacity of GAC were examined. It was found that after several adsorption/MW regeneration cycles, the adsorption rate of GAC increased, whereas, the adsorption capacity decreased, which could be explained according to the change of textural properties. Most of the PCB29 adsorbed on GAC was degraded within 3min under MW irradiation, and the analysis of degradation products by GC-MS demonstrated that PCB29 experienced dechlorination during this treatment.
本研究考察了颗粒活性炭（GAC）吸附和微波（MW）再生处理模拟土壤洗涤液中2,4,5-三氯联苯（PCB29）的效果。PCB29的吸附过程在连续流动吸附柱中进行。吸附后，负载PCB29的GAC在103℃下干燥，并在石英反应器中通过2450MHz的MW以700W照射5分钟进行再生。通过测定连续吸附/MW再生循环中PCB29的吸附速率和吸附量来分析该过程的效果。考察了再生对GAC的结构性质和PCB29吸附容量的影响。结果发现，经过几次吸附/MW再生循环后，GAC的吸附速率增加，而吸附容量降低，这可以根据结构性质的变化来解释。在MW照射下，吸附在GAC上的大部分PCB29在3分钟内降解，通过GC-MS对降解产物的分析表明，PCB29在该处理过程中发生了脱氯反应。
