摘要
热活化过硫酸盐(Heat/PDS)体系因能有效去除垃圾渗滤液浓缩液中溶解性有机物(DOM)而备受关注,但限于此类实际废水组分极其复杂,其转化机理尚需进一步研究.本文采用具有超高分辨率的静电场轨道阱质谱从分子组成的角度研究了垃圾渗滤液浓缩液中DOM在Heat/PDS体系的转化特性.结果表明,经Heat/PDS体系处理后,垃圾渗滤液浓缩液中DOM分子式从3732种减少至2984种,出水中DOM具有低芳香性、高饱和程度和高氧化程度的特性,降解途径包括:去芳香化、去甲基化、氢提取和羧化反应等.此外,出水中DOM包含1837种未知氯代有机物(CHOCl、CHONCl、CHOSCl和CHONSCl类),其前驱体主要为垃圾渗滤液浓缩液中DOM氧化降解的中间产物,如低氧高度不饱和酚类及脂肪族DOM.本研究可为垃圾渗滤液浓缩液中DOM的处理和氯代有机物的阻控提供一定理论依据.
Heat-activated persulfate(Heat/PDS)process is of great interest for the effective removal of dissolved organic matter(DOM)from landfill leachate concentrates,but the transformation mechanism needs to be further investigated due to the extremely complex components.In this study,an Orbitrap Fusion MS with ultra-high resolution was used to study the transformation characteristics of DOM in landfill leachate concentrates in the Heat/PDS process from the perspective of molecular composition.The results showed that the molecular formulae of DOM in landfill leachate concentrates amounted to 3732,and after treatment with Heat/PDS process,the molecular formulae of DOM were reduced to 2984,with the characteristics of low aromaticity,high saturation,and high oxidation,and the main degradation pathways included dearomatization,demethylation,hydrogen extraction,and carboxylation reactions.In addition,the DOM in the Heat/PDS treated effluent contained 1837 unknown chlorinated DOM,mainly CHOCl,CHONCl,CHOSCl,and CHONSCl,whose precursors were mainly intermediates of oxidative degradation of DOM in landfill leachate concentrates with low-oxygen highly unsaturated or phenolic structures and aliphatic structures.This study provides theoretical basis for the treatment of landfill leachate concentrates and the prevention-control of chlorinated DOM.
作者
陈炜鸣
辜哲培
何晨
李启彬
CHEN Weiming;GU Zhepei;HE Chen;LI Qibin(Faculty of Geosciences and Environmental Engineering,Southwest Jiaotong University,Chengdu 611756;State Key Laboratory of Heavy Oil Processing,China University of Petroleum,Beijing 102249)
出处
《环境科学学报》
CAS
CSCD
北大核心
2023年第8期122-130,共9页
Acta Scientiae Circumstantiae
基金
四川省自然科学基金(No.2023NSFSC0350)
中央高校基本科研业务费-科技创新项目(No.2682022CX037)。
关键词
垃圾渗滤液浓缩液
热活化过硫酸盐体系
溶解性有机物
降解途径
转化机制
landfill leachate concentrates
heat-activated persulfate process
dissolved organic matter
degradation pathway
transformation mechanism
