改性污泥和小球藻共热解生物炭对四环素的吸附性能研究  

Study on tetracycline adsorption properties of modified sludge and chlorella copyrolysis biochar

作　　者：张学俊 田永静[1] 王宇航 ZHANG Xuejun;TIAN Yongjing;WANG Yuhang(School of Environmental Science and Engineering,SUST,Suzhou 215009,China)

机构地区：[1]苏州科技大学环境科学与工程学院,江苏苏州215009

出　　处：《苏州科技大学学报（工程技术版）》2024年第3期39-48,共10页Journal of Suzhou University of Science and Technology（Engineering and Technology Edition）

基　　金：水体污染控制与治理科技重大专项(2017ZX07205001)。

摘　　要：以城市污水污泥和小球藻在高温下共热解,通过FeCl_(2)·4H_(2)O、尿素和KOH进行改性处理,分别制备原始生物炭(SCBC)、铁氮负载生物炭(Fe_(2)NSCBC)、碱二次改性生物炭(KFe_(2)NSCBC),用以吸附四环素(TC)。结果表明,KFe_(2)NSCBC在吸附速率、吸附容量、去除率方面表现都优于Fe_(2)NSCBC和SCBC。当条件为pH=3,TC浓度为200 mg/L,投加量为2.0 g/L时KFe_(2)NSCBC对TC的去除率高达98.51%。表征结果显示,KFe_(2)NSCBC具有更大的比表面积,更丰富的孔隙结构,同时改性后官能团增多,铁氧官能团(Fe_(3)O_(4))和氮氧官能团成功负载。KFe_(2)NSCBC的吸附行为属于吸热且主动的反应,传质过程满足颗粒内扩散型,等温吸附过程与Langmuir和Freundlich模型符合度都很高,在45℃时的饱和吸附量为315.75 mg/g。KFe_(2)NSCBC对吸附TC前后表征对比分析,表明孔径扩散、π-π键、静电反应和氢键以及络合反应共同影响KFe_(2)NSCBC对TC的吸附过程。Municipal sewage sludge and chlorella were co-pyrolyzed at high temperature and modified by FeCl_(2)·4H_(2)O,urea and KOH to prepare the original biochar(SCBC),iron nitrogen supported biochar(Fe_(2)NSCBC)and alkali secondary modified biochar(KFe_(2)NSCBC),respectively,for the adsorption of tetracycline(TC).The results showed that KFe_(2)NSCBC was superior to Fe_(2)NSCBC and SCBC in terms of adsorption rate,adsorption capacity and removal rate.When pH=3,TC concentration is 200 mg/L and dosage is 2.0 g/L,the removal rate of TC by KFe_(2)NSCBC is 98.51%.The characterization results show that KFe_(2)NSCBC has a larger specific surface area and more abundant pore structure.Meanwhile,after modification the functional groups are increased,and the ferric oxygen functional groups(Fe_(3)O_(4))and nitrogen oxygen functional groups are successfully loaded.The adsorption behavior of KFe_(2)NSCBC is endothermic and active,and the mass transfer process meets the intra-particle diffusion type.The isothermal adsorption process is in good agreement with Langmuir and Freundlich models,and the saturation adsorption capacity at 45℃is 315.75 mg/g.Comparative analysis of the characterization of TC before and after adsorption by KFe_(2)NSCBC showed that pore diffusion,π-πbond,electrostatic reaction,hydrogen bond and complex reaction all affected the adsorption process of TC by KFe_(2)NSCBC.

关 键 词：共热解生物炭 吸附四环素 生物炭改性 吸附机理 

分 类 号：X703[环境科学与工程—环境工程]