P改性生物炭微生物复合材料磷释放特性与阿特拉津去除效果及机理研究  

Phosphorus release characteristics and atrazine removal effect and mechanism of phosphorus modified biochar-microbial composites

作　　者：王宣懿 梁媛[1] 袁楚齐 程媛媛[1] WANG Xuanyi;LIANG Yuan;YUAN Chuqi;CHENG Yuanyuan(School of Environmental Science and Engineering,Suzhou University of Science and Technology,Suzhou 215009)

机构地区：[1]苏州科技大学环境科学与工程学院,苏州215009

出　　处：《环境科学学报》2024年第6期20-30,共11页Acta Scientiae Circumstantiae

基　　金：2022姑苏乡土人才项目;苏州市关键核心技术攻关(社会发展)项目(No.2023SS06)。

摘　　要：为了实现农田土壤中降污增肥协同增效的目标,本研究采用KH2PO4浸渍热解得到P改性生物炭PBC,并将阿特拉津降解菌D2负载在PBC上制备了生物炭-微生物复合材料DPBC.通过Heldey-P提取法研究材料的磷释放特征,通过吸附解吸实验研究材料对阿特拉津的去除效果,并通过FTIR、生物量以及细胞膜的透过性等探究对阿特拉津的去除机理.结果表明,DPBC总P含量为6.971 mg·g^(-1),是普通生物炭微生物复合DBC的9.67倍.在72 h P总释放量约为30.4%,DPBC的P缓释特性主要是由于其具有多孔的结构对P的吸持以及结晶性磷酸盐的缓慢释放.相较于DBC,DPBC对阿特拉津的去除效果更好,2.5 h可将50 mg·L^(-1)的阿特拉津完全去除,一方面是由于PBC的更大的比表面积、丰富的官能团、降低的pH等有利于D2的负载和对阿特拉津的有效吸附,其次,P改性生物炭可提供更多的P元素不仅促进了降解菌D2的生长,还有利于缓解ATZ对D2细胞膜脂质的过氧化损伤,从而提高了D2对阿特拉津的去除能力及耐受能力.根据降解产物推测DPBC去除阿特拉津的主要通过脱氯羟基化、脱甲基化、脱烷基化等过程最终生成毒性较低的三聚氰胺二酰胺.因此,DPBC是一种高效、稳定、绿色的降污增肥绿色产品.To achieve the synergetic effect of pollutant reduction and fertilizer enhancement in agricultural soil,we employed KH2PO4 impregnation and pyrolysis techniques to obtain P-modified biochar(PBC)in this study.Furthermore,Atrazine degrading bacteria D2 were loaded onto PBC to fabricate a biochar-microbial composite termed DPBC.The phosphorus release characteristics were examined using the Heldey-P extraction method.Moreover,the atrazine removal efficiency of DPBC was assessed through adsorption and desorption experiments,alongside exploring the mechanisms underlying atrazine removal using FTIR,biomass,and membrane permeability analysis.Our findings unveiled that DPBC showcased a total P content of 6.971 mg·g^(-1),representing a staggering 9.67 times increment compared to DBC-a conventional biochar-microbial composite.Notably,after 72 hours,approximately 30.4%of the total P content was released,signifying the slow-release property of DPBC.This attribute can be primarily ascribed to the porous structure of DPBC and the gradual transformation of crystalline phosphate.Regarding atrazine removal,DPBC exhibited superior efficacy in contrast to DBC.Remarkably,it accomplished complete removal of 50 mg·L^(-1) atrazine within a mere 2.5 hours.This heightened efficiency can be attributed to the favorable surface properties of PBC.Specifically,the ample presence of functional groups on the PBC surface facilitated effective atrazine adsorption by DPBC.Additionally,PBC imparts supplementary phosphorus elements,thereby not only promoting the proliferation of D2-the atrazine degrading bacterium,but also mitigating lipid peroxidation damage encountered by D2 cell membranes resulting from atrazine exposure.Consequently,the removal capacity and atrazine tolerance of D2 were significantly bolstered.Moreover,through thorough analysis of degradation byproducts,it was inferred that DPBC predominantly expedites atrazine degradation via demethylation,dealkylation,and dechlorination hydroxylation,eventually yielding low-toxicity melamine

关 键 词：磷改性生物炭 微生物 磷缓释 阿特拉津 

分 类 号：X53[环境科学与工程—环境工程]