福建农林大学学报（自然科学版）2025，Vol.54Issue(3)：365-374,10.DOI:10.13323/j.cnki.j.fafu(nat.sci.).202406013
不同腐殖酸氧化还原产羟基自由基潜力及其对微塑料降解的影响
Hydroxyl radical production potential of various humic acids through oxidative reduction and their impacts on microplastic degradation
摘要
Abstract
[Objective]This study focused on the ability of humic acid(HA)from different sources to generate hydroxyl radicals(·OH)during redox process and their effectiveness in the oxidative degradation of polystyrene microplastics(PS-MPs),to provide a theoretical basis for a deeper understanding of the continuous production of·OH in microbial-mediated HA redox processes and its role in pollutant transformation.[Method]Bacillus thermotoleran SgZ-8 was selected as a model strain to establish HA redox cycle system using cow dung compost humic acid(dc-HA),chicken manure compost humic acid(cc-HA),and sludge compost humic acid(sc-HA).Fourier transform infrared spectroscopy(FTIR),3-dimensional fluorescence spectroscopy,X-ray photoelectron spectroscopy(XPS),and other techniques were employed to analyze the structure,functional groups,·OH generation capacity of HA,and the impact of different HA on the degradation of PS-MPs.[Result]dc-HA,cc-HA and sc-HA differed in structure,func-tional groups and·OH production capacity,among which dc-HA contained more oxygen-containing functional groups,such as qui-none and phenol groups,thus exhibiting stronger electron transfer ability and the highest·OH production capacity.Referring to Pearson′s correlation coefficient analysis,the·OH production capacity of HA was positively correlated with its total phenolic con-tent,electron donating capacity and H2O2 content.Characterization analysis of PS-MPs revealed an overall increase in the O/C ratio of all the 3 types of HA.Specifically,dc-HA had greater number of oxygen-containing groups with an increase of carbonyl index from 0.001 to 0.077.In addition,given higher·OH yields from the redox process,dc-HA had a better ability to degradate PS-MPs.[Conclusion]The differences between HA from different sources are primarily attributed to variations in their oxygen-containing func-tional groups,with the number of oxygen-containing groups being roughly positively correlated with their radical generation capacity and pollutant degradation ability.关键词
腐殖酸/分子结构/氧化还原循环/羟基自由基/聚苯乙烯微塑料Key words
humic acid/molecular structure/redox cycle/hydroxyl radical/polystyrene microplastics分类
环境科学引用本文复制引用
刘钰洁,陈祖森,崔骏凯,陈泽伟,吴杰峰,曾秋婷,陈志..不同腐殖酸氧化还原产羟基自由基潜力及其对微塑料降解的影响[J].福建农林大学学报（自然科学版）,2025,54(3):365-374,10.基金项目
福建农林大学科技创新专项(CXZX2020068A). （CXZX2020068A）
