硫化锰活化氧气产生活性氧的种类、动力学及反应机制  

Activation of oxygen by manganese sulfide to produce reactive oxygen:Species,kinetics and reaction mechanisms

作　　者：李佳宁 袁艺博 张峻达 李宁 郭钦 余扬逸 黄倩倩 魏西鹏 江进 LI Jianing;YUAN Yibo;ZHANG Junda;LI Ning;GUO Qin;YU Yangyi;HUANG Qianqian;WEI Xipeng;JIANG Jin(School of Ecology,Environment and Resources,Key Laboratory for City Cluster Environmental Safety and Green Development of the Ministry of Education,Guangdong University of Technology,Guangzhou 510006,P.R.China;School of Environment,South China Normal University,Guangzhou 510006,P.R.China;School of Environment and Energy,South China University of Technology,Guangzhou 510006,P.R.China;Department of Water Ecology and Environment,Pearl River Water Resources Research Institute,Guangzhou 510611,P.R.China)

机构地区：[1]广东工业大学生态环境与资源学院,大湾区城市环境安全与绿色发展教育部重点实验室,广州510006 [2]华南师范大学环境学院,广州510006 [3]华南理工大学环境与能源学院,广州510006 [4]珠江水利委员会珠江水利科学研究院水生态环境研究所,广州510611

出　　处：《土木与环境工程学报(中英文)》2025年第2期221-231,共11页Journal of Civil and Environmental Engineering

基　　金：国家自然科学基金(42207244);广东省自然科学基金(2022A1515010195)。

摘　　要：铁/锰硫矿物广泛存在于缺氧地下环境中,铁(Fe)、锰(Mn)和硫(S)元素的循环过程控制着地下环境的物质循环和能量转化过程。氧气(O_(2))扰动下,铁硫矿物可通过双电子路径还原O_(2),产生活性氧(ROS),但锰硫矿物与O_(2)反应产生ROS的反应过程还不清楚。以自然界中普遍存在的典型锰硫矿物硫化锰(MnS)为研究对象,探究MnS活化O_(2)产生ROS的种类、动力学原理及反应机制。结果表明,MnS可以活化O_(2)产生大量ROS,包括羟基自由基(·OH)、过氧化氢(H_(2)O_(2))和超氧阴离子自由基(O_(2)^(·-));相同条件下,MnS/O_(2)体系中产生·OH累积量高达389.0μmol/L,其产量分别为相同浓度马基诺矿(FeS)和黄铁矿(FeS_(2))体系的4.4、149.6倍;O_(2)首先被MnS提供的单电子还原,产生O_(2)^(·-),继而再获得一个电子,生成H_(2)O_(2);溶解性Mn2+催化O_(2)/H_(2)O_(2)产生·OH的效率比较低,但结构态Mn(Ⅱ)可以高效催化H_(2)O_(2)产生·OH,因此,非均相催化H_(2)O_(2)是产生·OH的重要途径;溶解性的S^(2-)将电子传递至高价态的Mn(Ⅲ)/Mn(Ⅳ),促进了结构态Mn(Ⅱ)的再生,强化了Mn(Ⅱ)/Mn(Ⅲ)电子循环,进而提升了·OH的产生效率;以苯酚为目标污染物,MnS/O_(2)体系3 h内对5 mg/L苯酚的降解效率高达97.4%,表明利用MnS活化O_(2)具有较好的环境修复应用前景。Iron/manganese sulfides exist widely in the anoxic underground environment.The element cycling process of Fe,Mn and S controls the material cycling and energy conversion process in the underground environment.Usually,iron sulfides can produce reactive oxygen species(ROS)with O_(2) disturbance by providing electrons to reduce O_(2).However,the specific mechanism of ROS production by the reaction between manganese sulfides and O_(2) is still unclear.Herein,manganese sulfide(MnS),a prevalent natural form of manganese sulfide minerals,was studied to explore the species,kinetics and reaction mechanisms of ROS generated by the activation of O_(2) by MnS.The results showed that MnS could activate O_(2) to produce a large number of ROS,including·OH,H_(2)O_(2) and O_(2)^(·-).The maximum cumulative·OH reached 389.0μmol/L using 1 g/L MnS with initial pH 3 at 200 r/min stirring speed,and the yield of·OH was 4.4 and 149.6 times greater than that of FeS and FeS_(2) oxygenation under the same molar concentration,respectively.The reduction of O_(2) by MnS resulted in the generation of O_(2)·-through the transfer of single electron,followed by the acquisition of an additional electron to form H_(2)O_(2).The dissolved Mn^(2+) catalyzed O_(2)/H_(2)O_(2) to produce·OH with low efficiency,but the structural Mn(II)could efficiently catalyze H_(2)O_(2) to produce abundant·OH,indicating that heterogeneous catalysis of H_(2)O_(2) played an important role in·OH production.Additionally,the soluble S^(2-)might facilitate electrons transfer to high-valence Mn(Ⅲ)/Mn(Ⅳ)to promote the regeneration of structural Mn(Ⅱ),which further promoted the production efficiency of·OH via strengthening the electron cycle of Mn(Ⅱ)/Mn(Ⅲ).Furthermore,the degradation efficiency of phenol(5 mg/L)by MnS/O_(2) system was up to 97.4%within 3 h,indicating that the activation of O_(2) by MnS showed great potential in the environmental remediation.

关 键 词：硫化锰 氧气 羟基自由基 过氧化氢 结构态Mn(Ⅱ) 

分 类 号：X53[环境科学与工程—环境工程]