高卤染料废水采用UV/SO_(3)^(2-)工艺减毒过程中的中间产物及其毒性变化规律研究  

Variation of Intermediates and Toxicity in High Halogen Dye Wastewater During UV/SO_(3)^(2-)Process for Detoxification

作　　者：任航 熊富忠 李菲菲[1] 陈吕军[1] Ren Hang;Xiong Fuzhong;Li Feifei;Chen Lyujun(School of Environment,Tsinghua University,Beijing 100084,China;College of Environmental Sciences and Engineering,Peking University,Beijing 100871,China)

机构地区：[1]清华大学环境学院,北京100084 [2]北京大学环境科学与工程学院,北京100871

出　　处：《生态毒理学报》2023年第6期225-236,共12页Asian Journal of Ecotoxicology

基　　金：国家自然科学基金资助项目(52070111)。

摘　　要：染料废水含有大量难降解有机污染物,其中的有机卤代物通常具有较大的毒性和生态风险,但这类物质在常规的生物处理和化学处理工艺中的去除效果不佳。针对染料废水的脱卤困境,研究采用UV/SO_(3)^(2-)高级还原工艺对染料废水进行还原脱卤。在初始pH为8.5,SO_(3)^(2-)投加量为40 mmol·L^(-1)的条件下,废水中52.2%的可吸附有机卤素(adsorbable organic halogens,AOX)可以在反应开始6 h后被去除,更高的初始pH和更大的SO_(3)^(2-)投加量均有利于提升AOX的去除率。中间体的定性和半定量研究揭示了染料废水中部分氯代苯胺类物质的还原脱卤路径,发现苯胺很可能是这些物质还原脱卤的主要产物。废水中有机物的平均预测毒性揭示了还原过程中废水急性毒性的变化趋势。这一趋势与T_(3)发光杆菌和小球藻的急性毒性评价结果一致。此外,染料废水的AOX浓度与T_(3)发光杆菌的发光抑制率呈现正相关关系,而且染料废水经过还原脱卤后,尽管水中盐含量有所增加,其EC_(50)由1.26 mg·L^(-1)增加到5.94 mg·L^(-1),这也证明了还原脱卤过程可以降低出水的急性毒性。因此,UV/SO_(3)^(2-)过程可以通过对水中有机卤代物的还原脱卤降低出水中的AOX,降低废水急性毒性和生态风险。Many refractory organic contaminants are contained in dye wastewater,especially the organic halogens,which are considered toxic and ecologically risky.Their removal is unsatisfactory by conventional bioreactors and chemical process.In this study,UV/SO_(3)^(2-),one of the advanced reduction processes,was selected to address this dehalogenation trouble in dye wastewater treatment.When the initial pH of dye wastewater is 8.5 and SO_(3)^(2-)dosage is 40 mmol·L^(-1),52.2%of adsorbable organic halogens(AOX)will be removed within 6 h.Higher initial pH value and higher SO_(3)^(2-)dosage are favorable to dehalogenation.The identification and relative quantification of intermediates revealed the dehalogenation pathway of polychlorinated aniline,and aniline may be the main reducing product.The toxicity reduction was indicated by the variation of average predicted acute toxicity value of multiple organic compounds,which was complied with the result of acute toxicity evaluation by Photobacterium phosphoreum T_(3) and Chlorella pyrenoidosa.The positive correlation between the luminescence inhibition rate and AOX concentration is verified,and the EC_(50) of this high-halogen dye wastewater increases from 1.26 mg·L^(-1)to 5.94 mg·L^(-1)after dehalogenation,accompanied with increasing salinity.Acute toxicity reduction during UV/SO_(3)^(2-)process is revealed.Therefore,the UV/SO_(3)^(2-)process has been proven to decrease AOX and acute toxicity in dye wastewater.

关 键 词：染料废水 可吸附有机卤素 毒性评价 高级还原 UV/SO_(3)^(2-) 

分 类 号：X171.5[环境科学与工程—环境科学]