生物炭和沼液DOM与Pb(Ⅱ)络合的二维相关光谱特性  

Characteristics of two-dimensional correlation spectroscopy on the binding Pb(II)onto DOM extracted from biochar and biogas slurry

作　　者：刘洋 王刚 戴本林[3] LIU Yang;WANG Gang;DAI Ben-lin(Laboratory and Equipment Management Department,Huaiyin Normal University,Huaian 223300,China;Joint Technology Transfer Center,Science and Technology Department,Huaiyin Normal University,Huaian 223300,China;Jiangsu Key Laboratory for Chemistry of Low-Dimensional,Huaiyin Normal University,Huaian 223300,China)

机构地区：[1]淮阴师范学院实验室与设备管理处,江苏淮安223300 [2]淮阴师范学院联合技术转移中心,科学技术处,江苏淮安223300 [3]淮阴师范学院江苏省低维材料化学重点实验室,江苏淮安223300

出　　处：《化学研究与应用》2023年第4期834-841,共8页Chemical Research and Application

基　　金：国家自然科学基金项目(51808250)资助;江苏省自然科学基金项目(BK20160430)资助。

摘　　要：本文采用荧光猝灭滴定结合二维相关光谱和移动窗口二维相关光谱比较分析生物炭和沼液中溶解性有机物(DOM)与重金属Pb(Ⅱ)的络合特性。研究结果表明,生物炭DOM主要以类腐殖酸为主,而沼液DOM以类蛋白物质为主;生物炭DOM在387nm处的类腐殖酸组分能够优先与Pb(Ⅱ)络合,其次是467nm和538nm处的类腐殖酸,最后是类蛋白荧光物质;沼液DOM组分与Pb(Ⅱ)络合的优先次序依次为282→422→409→366→328→376nm。研究结果也表明,对二维相关光谱同步和异步的1/n次转换光谱能够清晰地识别出被掩盖的荧光峰信息,且能够保留原来光谱信息的络合次序。生物炭DOM与Pb(Ⅱ)的络合物在90~160μM·L^(-1)之间分别在309nm、335nm、387nm、432nm和467nm发生构象变化。沼液DOM与Pb(Ⅱ)的络合物分别在282nm和328nm处发生了构象变化,构象变化的跃迁点在78μM·L^(-1)。生物炭DOM与Pb(Ⅱ)的lgK值在4.63~5.33之间,类富里酸与Pb(Ⅱ)的lgK值明显要低于类腐殖酸。沼液DOM与Pb(Ⅱ)的lgK值在3.96~4.33之间,其类蛋白荧光组分与Pb(Ⅱ)的络合物稳定性比类富里酸和类腐殖酸略高。In this work,the binding properties between Pb(II)and dissolved organic matter(DOM)extracted from biochar and biogas slurry were comparatively analyzed using fluorescence quenching titration in combination with two-dimensional correlation and moving window two-dimensional correlation spectroscopy.The results showed that the biochar DOM was mainly dominated by humiclike substances,while the biogas slurry DOM was dominated by protein-like substances.In the biochar DOM,humic-like component at 387 nm could preferentially complexate with Pb(II),followed by humic-like components at 467 nm and 538 nm,and finally the fluorescent protein-like materials.However,the preferential bonding of Pb(II)to the biogas slurry DOM fractions can be ordered as follows:282→422→409→366→328→376 nm.The results also indicated that synchronous and asynchronous maps obtained by the 1/9-th power transformation could distinctly identify the concealed fluorescence signals and retain the original spectral information on the binding sequence.The complexes of biochar DOM and Pb(II)underwent conformational transitions at 309 nm,335 nm,387 nm,432 nm and 467 nm when the concentration of Pb(II)was in the range of 90~160μM·L^(-1).Conformation transition of biochar DOM-Pb(II)complexes occurred at 282 nm and 328 nm,in a Pb(II)concentration of 78μM·L^(-1).The lgK values of biochar DOM-Pb(II)ranged from 4.63 to 5.33,and the complexes of fulvic-like substances and Pb(II)showed higher lgK value than these for humic-like substances.The lgK values for biogas slurry DOM-Pb(II)were in the range of 3.96~4.33,in which the stability of complexes were slightly higher for protein-like fluorescent component than fulvic-and humic-like substances.

关 键 词：生物炭 沼液 DOM Pb(Ⅱ) 二维相关光谱 

分 类 号：O657.3[理学—分析化学]