Core-Facility Center for Photochemistry & Nanomaterials, Department of Chemistry, Research Institute of Natural Sciences, Gyeongsang National University, Jinju, 52828, Republic of Korea.
Electronic Convergence Division, Korea Institute of Ceramic Engineering & Technology, 101, Soho-Ro, Jinju, 52851, Republic of Korea.
Environ Pollut. 2021 Dec 15;291:118158. doi: 10.1016/j.envpol.2021.118158. Epub 2021 Sep 14.
Chlorine-based compounds are typical persistent organic pollutants (POPs) that are widely generated in industrial production. This paper reports an effective and rapid pulsed laser irradiation technique for the dechlorination of hexachlorobenzene (HCB), a model pollutant, without additional catalysts or supports. The effects of the laser parameters, including the laser wavelength and power, on the dechlorination efficiency, were also investigated. The optimized results showed that a lower laser wavelength of 266 nm with 10 mJ/pulse power exhibited the highest dechlorination efficiency with 95% within 15 min. In addition, the laser beam effect was examined by designing the direct-pulsed laser single and multipath irradiation system. The results showed that improving the laser beam profile resulted in more than 95% dechlorination efficiency within 5 min. Thus, the dechlorination reaction proceeded much faster as the surface area that the laser beam came in contact with increased due to the multipath system than the single pathway. Gas chromatography identified benzene as the final product of HCB with pentachlorobenzene (PCB), tetrachlorobenzene (TeCB), trichlorobenzene (TCB), dichlorobenzene (DCB), and chlorobenzene (CB) as intermediate products. The mechanism of HCB dechlorination was explained by a comparison of theoretical calculations with the experimental results. The present study reports an advanced technique for the complete dechlorination of chlorobenzenes, which holds great application potential in environmental remediation.
基于氯的化合物是典型的持久性有机污染物（POPs），广泛存在于工业生产中。本文报道了一种有效且快速的脉冲激光辐照技术，用于脱除六氯苯（HCB）这种模型污染物中的氯，该过程无需添加额外的催化剂或载体。还研究了激光参数（包括激光波长和功率）对脱氯效率的影响。优化结果表明，在 15 分钟内，波长为 266nm、功率为 10mJ/脉冲的激光具有最高的脱氯效率，可达 95%。此外，通过设计直接脉冲激光单路径和多路径辐照系统，考察了激光束的作用。结果表明，改善激光束形貌可使脱氯效率在 5 分钟内超过 95%。因此，多路径系统比单路径系统使激光束与表面的接触面积增大，导致脱氯反应的速度大大加快。气相色谱鉴定 HCB 的最终产物为苯，中间产物为五氯苯（PCB）、四氯苯（TeCB）、三氯苯（TCB）、二氯苯（DCB）和氯苯（CB）。通过理论计算与实验结果的比较，解释了 HCB 脱氯的机理。本研究报道了一种先进的脱除氯苯的技术，在环境修复方面具有很大的应用潜力。
