不同粒径生物炭和微塑料共存对菲吸附的影响  

Effects of the coexistence of biochar and microplastic in different particle sizes on phenanthrene sorption

作　　者：迟杰[1] 邢海文 张海彤 童银栋[1] CHI Jie;XING Haiwen;ZHANG Haitong;TONG Yindong(School of Environmental Science and Engineering,Tianjin University,Tianjin 300350,China)

机构地区：[1]天津大学环境科学与工程学院,天津300350

出　　处：《农业环境科学学报》2022年第3期616-621,共6页Journal of Agro-Environment Science

基　　金：国家自然科学基金项目(41977324)。

摘　　要：为研究环境中生物炭和微塑料之间的相互作用对有机污染物吸附产生的影响,选取两种粒径范围[0.85~2.00 mm(L)和0.11~0.18 mm(S)]的小麦秸秆生物炭(BC)和聚乙烯微塑料(PE),对其性质进行表征,并测定了吸附平衡溶液中溶解性有机碳的浓度和组成,研究了其单独和共存时吸附菲的行为。结果表明:同种颗粒物不同粒径间的差异主要体现在总比表面积、孔结构和表面官能团数量;SBC的总比表面积(216.32 m^(2)·g^(-1))约是LBC(2.31 m^(2)·g^(-1))的100倍,而LBC的平均孔径(8.92 nm)约是SBC(2.28 nm)的4倍;SPE的总比表面积(0.17 m^(2)·g^(-1))是LPE(0.07 m^(2)·g^(-1))的2倍多。SBC羟基振动峰(3400 cm^(-1))的强度显著高于LBC;SPE亚甲基振动峰的强度高于LPE。吸附等温线结果显示,颗粒物对菲的吸附均符合Freundlich模型(R2>0.94);单一颗粒物吸附菲能力(lg Kf)的顺序为SBC>SPE>LPE>LBC;当生物炭与聚乙烯微塑料共存时吸附能力强于单一颗粒物,并且高于两相Freundlich模型预测值,说明菲在生物炭与聚乙烯微塑料混合颗粒物上的吸附不是独立的;同时,混合颗粒物吸附平衡溶液中溶解性有机碳的浓度和芳香度明显下降,并且溶解性有机碳浓度与颗粒物的lg Kf显著负相关,说明不同颗粒物对菲的吸附不仅受颗粒物表面性质的影响,还受溶解性有机碳的控制。Biochar and microplastics normally coexist in the environment,and the interactions between them can influence their sorption of organic pollutants.In this study,polyethylene(PE)and wheat straw biochar(BC)with particle size ranging between 0.85~2.00 mm and 0.11~0.18 cm were selected and named as LPE,SPE,LBC,and SBC,respectively.The properties of these particles were characterized.The concentration and composition of dissolved organic carbon in the equilibrium solution was determined,and the phenanthrene sorption behavior in response to single or mixed particles was studied.The results showed that there were significant differences in the total specific surface area,pore structure,and contents of the surface functional groups between particles of different sizes.The total specific surface area of SBC(216.32 m^(2)·g^(-1))was approximately100 times as much as that of LBC(2.31 m^(2)·g^(-1)).The average pore diameter of LBC(8.92 nm)was approximately 4 times as much as that of SBC(2.28 nm).The total specific surface area of SPE(0.17 m^(2)·g^(-1))was as much as double of that of LPE(0.07 m^(2)·g^(-1)).As expected,the peak intensity of-OH vibrations in SBC(3400 cm^(-1))was stronger than that in LBC and the peak intensity of the-CH2 vibrations was stronger in SPE than in LPE.The sorption isotherms demonstrated that phenanthrene sorption on particles,fit well with the Freundlich model(R2>0.94).The sorptive ability(lg Kf)of a single particle of phenanthrene,was in the order of SBC>SPE>LPE>LBC.When BC and PE microparticles coexist,the lg Kf value was higher than what was predicated by the sum of the independent sorption values of BC and PE,indicating that the sorption of phenanthrene on mixed particles does not occur independently;meanwhile,the concentration and aromaticity of dissolved organic carbon was largely reduced.Additionally,concentration of dissolved organic carbon was negatively correlated with the lg Kf value.These results all suggest that phenanthrene sorption on different particles is affected not only by th

关 键 词：生物炭 微塑料 共存 吸附 溶解性有机碳 多环芳烃 

分 类 号：TQ426[化学工程] X505[环境科学与工程—环境工程]