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采用紫外活化过硫酸钠(UV/PS)降解三氯卡班(TCC).考察了UV、PS和UV/PS联用工艺去除TCC的效果,研究了PS投加量、反应初始pH值和腐殖酸(HA)等因素对UV/PS降解TCC的影响,推测了UV/PS工艺中TCC可能的降解途径,并对比了UV/PS和UV/H2O2工艺对TCC的去除效果和经济性.研究表明:UV与PS联用能够高效去除TCC,其降解过程符合拟一级动力学模型(R2≥0.95);拟一级反应速率常数k随着PS投加量的增加先增大再减小,在PS投加量为250μmol/L时,k达到最大值0.0810min-1;偏酸性条件(pH=6.0)有利于TCC的降解;HA对TCC的降解有抑制作用,抑制作用与HA的浓度呈正相关;GC/MS鉴定表明,TCC降解过程中主要的中间产物有异氰酸4-氯苯酯和对氯苯胺,其可能的降解途径为TCC分子结构中与酮羰基相连的C-N键断裂,脱氯,经过一系列的反应形成对氯苯胺和异氰酸4-氯苯酯;UV/PS降解TCC过程中溶液中脱氯反应导致Cl-浓度增加;与UV/H2O2工艺相比,相同条件下UV/PS工艺中k值增大了96.65%,单位电能消耗量提高了97%.“,”Triclocarban (TCC) in aqueous solution was degraded by UV-activated persulfate. The removal efficiency of TCC by direct UV irradiation, PS oxidation alone, and UV/PS process was compared in this experiment. The effect of PS dosage, initial pH and HA on TCC degradation by UV/PS was investigated. The possible degradation approach and intermediates was proposed, meanwhile, the effect of degradation and economical efficiency for UV/PS were compared with UV/H2O2. The results showed that UV irradiation-activated sodium persulfate process could remove TCC efficiently and TCC degradation followed the pseudo-first order kinetic model well (R2≥0.95). The pseudo-first-order-constantk increased firstly and then decreased with the increase of PS dosage. The value ofk reached a maximum of 0.0810min-1 when the dosage of PS was 250μmol/L. Slightly acidic condition (pH=6.0) was better for TCC degradation. The removal of TCC was inhibited in the presence of HA, and the effect of inhibition was significantly positively correlated with the concentration of HA. 1-chloro-4-isocyanato-benzen and 4-chloroaniline were identified as the main intermediates by GC/MS. The possible degradation approach is that the C-N chemical bonds of the keto carbonyl group were broken during the degradation process, and thus 1-chloro-4-isocyanato-benzen and 4-chloroaniline was generated via the dechlorination and other reactions. The concentration of Cl- was increased through the degradation process of TCC by UV/PS. Compared with UV/H2O2 process, the pseudo-first-order-constantk and the electrical energy per order of UV/PS process increased by 96.65% and 97%, respectively.