摘要
氯苯是产生二噁英的主要前驱物。利用脉冲电晕等离子去除三氯苯,从电源参数电压、频率、脉宽、上升沿几个方面探讨了其对三氯苯去除效果及作用机理。结果表明:1)在输入电压16 k V,频率300 Hz,脉宽100 ns,上升/下降沿100 ns的条件下,三氯苯去除率最高可达70%左右。2)当输入频率500 Hz,脉宽100 ns,上升/下降沿100 ns时,三氯苯去除率随着电压升高增大;当输入电压分别为14,16 k V,脉宽100 ns,上升/下降沿100 ns时,调节频率为100~800 Hz,随着频率升高,三氯苯去除率增大,继续增加频率,三氯苯去除率不变。3)脉宽和上升沿对三氯苯的处理效果影响不大。同时对脉冲电晕等离子体降解三氯苯的机理进行探讨,认为其降解主要是通过巨大能量引起断键脱氯脱氢,其次是氧化。
As a major precursor of dioxins,trichlorobenzene removal by pulse corona plasma was discussed in this paper. The effect of plasma on removal of trichlorobenzene was also investigated from the aspects of voltage,frequency,pulse width and rising edge of power supply parameters. The removal mechanism was also discussed. The results showed that: the removal efficiency of trichlorobenzene could be up to 70% at an input voltage of 16 k V,a frequency of 300 Hz,a pulse width of 100 ns,and a rising/falling edge of 100 ns. At the conditon of frequency 500 Hz,pulse width 100 ns,rising/falling edge 100 ns,trichlorobenzene removal efficiency increased with voltage; and at the conditon of pulse width 100 ns,rising/falling edge 100 ns,input voltage of 14 kV and 16 kV, in regulation frequency range of 100 ~ 800 Hz, the removal efficiency of trichlorobenzene increased as the frequency increased,and stayed stable if regulation frequency exceeded 800 Hz. Pulse width and rising edge had little effect on treatment effect of trichlorobenzene. It was believed that the trichlorobenzene degradation might be mainly caused by debonding and dehydrogenation of the bond,followed by oxidation.
引文
[1]张杰.焚烧处置危险废物产生二噁英的控制[J].探索科学,2016(5):238.
[2]李锻,刘明辉,吴彦,等.双极性脉冲高压介质阻挡放电降解氯苯和甲苯[J].中国环境科学,2006,26(增刊1):23-26.
[3]胡胜.新型脉冲电源研制及其处理六氯苯废水的研究[D].武汉:华中科技大学,2011.
[4]王勇.滑动弧等离子体降解氯苯类有机污染物的实验研究[D].杭州:浙江大学,2013.
[5]苏飞.介质阻挡放电等离子体降解氯苯的工艺特性及产物调控[D].杭州:浙江工业大学,2014.
[6]姜理英,曹书岭,朱润晔,等.介质阻挡放电对氯苯的降解特性及其产物分析[J].环境科学,2015,36(3):831-838.
[7]毛玉波.低温等离子体-催化降解氯苯的工艺特性及产物研究[D].杭州:浙江工业大学,2015.
[8]张丽军.低温等离子体协同处理含汞废气和二噁英的研究[D].北京:华北电力大学(北京),2017.
[9]马铭峰.等离子体技术协同控制汞和类二噁英物质研究[D].北京:中国矿业大学,2018.
[10]Zhou Y X,Yan P,Cheng Z X,et al.Application of non-thermal plasmas on toxic removal of dioxin-contained fly ash[J].Powder Technology,2003,135/136(3):345-353.
[11]Ren Y,Li X D,Ji S S,et al.Removal of gaseous Hx CBz by gliding arc plasma in combination with a catalyst[J].Chemosphere,2014,117(1):730-736.
[12]Ren Y,Li X D,Liang Y,et al.Degradation of PCDD/Fs in fly ash by vortex-shaped gliding arc plasma[J].Plasma Chemistry&Plasma Processing,2013,33(1):293-305.
[13]Chu W,Kwan C Y.The direct and indirect photolysis of 4,4'-dichlorobiphenyl in various surfactant/solvent-aided systems[J].Water Research,2002,36(9):2187-2194.
[14]Yan J H,Peng Z,Lu S Y,et al.Destruction of PCDD/Fs by gliding arc discharges[J].Journal of Environmental Science,2007,19(11):1404-1408.
[15]Hung P C,Chang S H,Chi K H,et al.Degradation of gaseous dioxin-like compounds with dielectric barrier discharges[J].Journal of Hazardous Materials,2010,182(1/2/3):246-251.
[16]Katsumata H,Kaneco S,Suzuki T,et al.Degradation of polychlorinated dibenzo-p-dioxins in aqueous solution by Fe(Ⅱ)/H2O2/UV system[J].Chemosphere,2006,63(4):592-599.
[17]Wang Z H,Wen Z C,Xu J R,et al.Theoretical study on destruction mechanism of 2,3,7,8-TCDD by O3and NO3[J].Chinese Journal of Chemical Physics,2010,23(3):303-309.
[18]Ge J L,Wang X H,Li C G,et al.Photodegradation of polychlorinated diphenyl sulfides mediated by reactive oxygen species on silica gel[J].Chemical Engineering Journal,2018.
[19]Chen J,Wu N N,Xu X X,et al.Fe(Ⅵ)-mediated singleelectron coupling processes for removal of chlorophene:a combined experimental and computational study[J].Environmental Science&Technology,2018,52(21):12592-12601.
[20]Sun X,Sun T,Zhang Q,et al.Degradation mechanism of PCDDs initiated by OH radical in Photo-Fenton oxidation technology:quantum chemistry and quantitative structure-activity relationship[J].Science of the Total Environment,2008,402(1):123-129.
[21]Lee J E,Choi W,Mhin B J,et al.Theoretical study on the reaction of OH radicals with polychlorinated dibenzo-p-dioxins[J].The Journal of Physical Chemistry A,2011,108(4):607-614.