摘要
为提高市政污水污泥(Sewage Sludge,SS)与赤泥(Red Mud,RM)的综合利用水平,探究其协同处置的资源化利用出路,以SS和RM为原料一步热解制备混合生物炭(Sludge-Red mud Mixed Biochar,SR MBC),经SR MBC活化过硫酸盐(Peroxysulphate,PS),强化其吸附降解废水中抗生素污染物环丙沙星(Ciprofloxacin,CIP)的能力。通过优化SR MBC的制备条件,分析pH值对SR MBC吸附降解CIP的影响,研究吸附降解动力学与热力学,并探讨该生物炭对CIP的去除效果及作用机制。结果显示:制得的混合生物炭对CIP的吸附质量比随热解温度的升高(500~800℃)而降低。其中SR MBC500对CIP的去除率和吸附质量比最高,分别为91%和6.09 mg/g。经SR MBC500中金属离子及官能团活化PS产生·SO-4自由基与吸附在SR MBC表面的CIP发生氧化反应,CIP去除率进一步提高,达99%。SR MBC对CIP的吸附效果受pH值影响较大,随pH值的升高,CIP的去除率先增加后减小;而经SR MBC活化PS后,吸附降解过程不再受pH值影响,在任意pH值下均可达到较高的去除率。SR MBC吸附CIP的过程符合拟二级动力学方程和Freundlich模型,且吸附过程是自发进行的,吸附机制包括孔隙扩散、静电作用、氢键作用和ππ堆积作用。SR MBC可在达到对SS和RM安全协同处置的同时,可通过活化PS进一步提高对CIP的去除率及吸附质量比,实现对抗生素高效去除的效果。
To improve the comprehensive utilization level of sewage sludge(SS)and red mud(RM),and explore the resource utilization way of their co-processing,a kind of mixed biochar(SR MBC)was prepared from SS and RM by one-step pyrolysis.SR MBC was used to activate persulfate(PS)to enhance the adsorption and degradation of ciprofloxacin(CIP)(a kind of antibiotic pollutant in wastewater).In this study,the preparation conditions of SR MBC were optimized,the effect of pH and biochar dosage on the adsorption and degradation of CIP by SR MBC was analyzed,and the kinetics and thermodynamics of adsorption and degradation were explored.Accordingly,the removal effect and mechanism of CIP by SR MBC were discussed.The results show that with the increase of pyrolysis temperature(500800℃),the specific surface area of SR MBC decreases,the peaks of functional groups such as—OH,C C,C O weaken,and the adsorption of CIP by SR MBC declines.The removal rate and adsorption capacity of CIP utilizing SR MBC500 are the highest,91%and 6.09 mg/g,respectively.Ascribed to the SO-4·radicals generated from the PS activating by the metal ions and functional groups of SR MBC500,the oxidation occurs with CIP adsorbed on the surface of SR MBC,and the removal rate of CIP further improves,reaching 99%.The adsorption effect of CIP by SR MBC is greatly affected by pH.With the increase in pH value,the removal of CIP first increases and then decreases.The optimal pH condition is 5.After activation of PS by SR MBC,SR MBC/PS exhibited wide adaptability to pH,and the adsorption and degradation process is no longer affected by pH,leading to a high removal rate at any pH value.The adsorption process of CIP on SR MBC follows the pseudo-second-order kinetics and Freundlich model,with the adsorption process occurring quickly.The adsorption mechanism includes pore diffusion,electrostatic interaction,hydrogen bonding interaction,andππstacking interaction.Compared with common biochar,SR MBC can not only achieve the co-processing of SS and RM but also further improve
作者
韩融
王成杰
郭亚凯
葛强茹
程阳
HAN Rong;WANG Chengjie;GUO Yakai;GE Qiangru;CHENG Yang(School of Water and Environment,Chang'an University,Xi'an 710054,China;Key Laboratory of Subsurface Hydrology and Ecological Effects in Arid Region,Ministry of Education,Chang'an University,Xi'an 710054,China)
出处
《安全与环境学报》
CAS
CSCD
北大核心
2023年第6期2069-2080,共12页
Journal of Safety and Environment
基金
国家自然科学基金青年基金项目(21407012)
陕西省自然科学基础研究计划项目(2021JM154)
中央高校基本科研业务费专项(300102298201)。
关键词
环境工程学
污泥
赤泥
生物炭
过硫酸盐
环丙沙星
environmental engineering
sludge
red mud
biochar
persulfate
Ciprofloxacin
