筛分浮选法高效提取土壤中聚乙烯微塑料研究  

Efficient Extraction of Polyethylene Microplastics from Soil by Sieve Flotation Method

作　　者：张杰[1] 赖金龙 罗学刚[1] ZHANG Jie;LAI Jinlong;LUO Xuegang(School of Life Science and Engineering,Southwest University of Science and Technology,Mianyang 621010,China;Engineering Research Center,Ministry of Education,Southwest University of Science and Technology,Mianyang 621010,China)

机构地区：[1]西南科技大学生命科学与工程学院,四川绵阳621010 [2]西南科技大学生物质材料教育部工程研究中心,四川绵阳621010

出　　处：《广东农业科学》2023年第3期89-96,共8页Guangdong Agricultural Sciences

基　　金：国民核生化防护国家重点实验室基础科研基金(SKLNBC2019-21)。

摘　　要：【目的】土壤中聚乙烯微塑料的高效分离、提取是研究聚乙烯微塑料环境污染、毒理等的关键环节,构建一种从土壤中原位分离、高效提取聚乙烯微塑料的分离方法。【方法】采用筛分浮选法、密度分离法和索氏提取法分别对土壤中的聚乙烯微塑料进行提取,计算3种分离方法对土壤中聚乙烯微塑料的提取率。采用扫描电子显微镜(SEM)分析聚乙烯微塑料表面微观形貌特征的变化;采用热重(TG)分析聚乙烯微塑料热解特性参数的变化;采用傅里叶红外光谱(FT-IR)分析聚乙烯微塑料特征官能团的变化。【结果】3种分离方法均可提取土壤中的聚乙烯微塑料,其中筛分浮选法的提取率最高可达95.58%,密度分离法的提取率最高可达89.60%,索氏提取法的提取率最高可达86.10%。SEM分析显示,索氏提取法分离的聚乙烯微塑料颗粒表面有细碎的鱼鳞纹或片状结构;密度分离法提取的聚乙烯微塑料表面附有大量的土壤杂质颗粒物;筛分浮选法分离的聚乙烯微塑料颗粒表面几乎没有土壤杂质,表面微观形貌特征未被破坏。TG和FT-IR分析显示,3种分离方法提取的聚乙烯微塑料主要成分均为聚乙烯微塑料且均没有破坏聚乙烯微塑料原有的官能团结构。【结论】3种分离方法的提取率为筛分浮选法>密度分离法>索氏提取法,微观表面特征完整性表现为筛分浮选法>密度分离法>索氏提取法,在提取率和保留提取物微观表面特征信息方面,筛分浮选法均优于其他两种分离方法。【Objective】Efficient separation and extraction of polyethylene microplastics from soil is a key link to study the behavior of polyethylene microplastics in terms of environmental pollution and toxicology,with a view to constructing a separation method for in situ separation and efficient extraction of polyethylene microplastics from soil.【Method】Polyethylene microplastics in soil were extracted by using sieve flotation method,density separation method and Soxhlet extraction method,and the extraction rate of polyethylene microplastics in soil was calculated by the three separation methods.Scanning electron microscopy(SEM)was used to analyze the changes of surface micromorphological features of polyethylene microplastics;thermogravimetric(TG)was used to analyze the changes of pyrolytic characteristic parameters of polyethylene microplastics;Fourier transform infrared spectroscopy(FT-IR)was used to analyze the changes of characteristic functional groups of polyethylene microplastics.【Result】All three separation methods can extract polyethylene microplastics from soil,with the highest extraction rate of 95.58%by sieve flotation method,89.60%by density separation method and 86.10%by soxhlet extraction method.SEM analysis showed that the surface of polyethylene microplastic particles separated by Soxhlet extraction method had fine fish scale pattern or flake structure;the surface of polyethylene microplastic extracted by density separation method had a large amount of soil impurity particles attached;the surface of polyethylene microplastic particles separated by sieve flotation method almost had no soil impurity and the surface microscopic morphological features were not destroyed.Thermogravimetric(TG)and Fourier infrared spectroscopy(FT-IR)analysis showed that the main components of polyethylene microplastics extracted by the three separation methods were all polyethylene microplastics and did not destroy the original functional group structure of polyethylene microplastics.【Conclusion】The extraction

关 键 词：微塑料 聚乙烯 提取方法 表面特征 土壤 筛分浮选法 地膜污染 

分 类 号：S153[农业科学—土壤学] X322[农业科学—农业基础科学]