酸改性酒糟生物炭对Cr(Ⅵ)的去除性能研究  

Study on the removal of Cr(Ⅵ)by acid-modified distillers’grains biochar

作　　者：唐恒军 邱彪 司马卫平 唐建 TANG Hengjun;QIU Biao;SIMA Weiping;TANG Jian(School of Civil Engineering,Sichuan University of Science&Engineering,Zigong 643000,China)

机构地区：[1]四川轻化工大学土木工程学院,四川自贡643000

出　　处：《工业水处理》2025年第3期144-151,共8页Industrial Water Treatment

基　　金：地质灾害防治与地质环境保护国家重点实验室开放基金项目(SKLGP2023K016);国家环境保护水土污染协同控制与联合修复重点实验室开放基金项目(GHBK-2022-003);国家环境保护重金属污染监测重点实验室开放基金项目(SKLMHM202311)。

摘　　要：利用白酒酒糟制备生物炭,采用KHCO_(3)活化后,再利用酸溶液浸渍进行改性,制备了酸改性酒糟生物炭(H-BC)。对H-BC的制备参数(热解温度、活化剂比例、改性酸种类及浓度)进行优化,得到热解温度为700℃,酒糟生物炭与活化剂(KHCO_(3))为1∶1.5,采用0.5 mol/L硝酸改性制备的H-BC对Cr(Ⅵ)的吸附性能最优。探讨了初始pH(2.0~6.0)、初始Cr(Ⅵ)质量浓度(100~600 mg/L)、吸附时间(0~27 h)、吸附温度(20~60℃)、背景离子等因素对H-BC吸附Cr(Ⅵ)效果的影响,结果表明,在pH=2.0时吸附性能最好,其吸附量为171.05 mg/g,去除率为86%;生物炭投加量为2.5 g/L时,Cr(Ⅵ)初始质量浓度为100~400 mg/L范围内酒糟生物炭表现出较好的吸附性能,H-BC的吸附量为151.36 mg/g,去除率为94.54%;吸附过程可分为快速吸附阶段(0~1 h)、缓慢吸附阶段(1~20 h)、平衡阶段(20~27 h);H-BC对Cr(Ⅵ)的吸附是一个吸热过程,吸附温度升高,吸附量随之增加;背景电解质(NaCl、KCl)浓度对Cr(Ⅵ)的吸附具有较大影响;吸附过程更符合Langmuir等温模型与准二级吸附动力学模型。H-BC对Cr(Ⅵ)的吸附机理涉及静电引力与氧化还原作用。The acid modified biochar(H-BC)was prepared with distillers’grains,which was activated by KHCO_(3)and modified by dipping in acid solution.By optimizing the preparation parameters of H-BC(pyrolysis temperature,activator ratio,type and concentration of modified acid),it was found that H-BC prepared at a pyrolysis temperature of 700℃and a mass ratio of distillers’grains biochar to activator(KHCO_(3))of 1∶1.5,and modified with 0.5 mol/L nitric acid had the best adsorption performance for Cr(Ⅵ).The effects of initial pH(2.0-6.0),initial Cr(Ⅵ)mass concentration(100-600 mg/L),adsorption time(0-27 h),adsorption temperature(20-60℃),background ions on the adsorption efficiency of H-BC for Cr(Ⅵ)were investigated.The results showed that the best adsorption performance was achieved at pH 2.0,with the adsorption capacity of 171.05 mg/g and the removal rate of 86%.When the initial mass concentration of Cr(Ⅵ)was 100-400 mg/L and the dosage of biochar was 2.5 g/L,the adsorption capacity of H-BC could reach 151.36 mg/g,with removal rate of 94.54%,demonstrating good adsorption performance within this concentration range.The adsorption process could be divided into rapid adsorption stage(0-1 h),slow adsorption stage(1-20 h),and equilibrium stage(20-27 h).The adsorption of Cr(Ⅵ)by H-BC was an endothermic process,and the adsorption amount increased with the increase of adsorption temperature.The concentration of background electrolytes(NaCl,KCl)had a significant impact on the adsorption of Cr(Ⅵ).The adsorption process was more in line with the Langmuir isotherm model and quasi second order kinetic model.The adsorption mechanism of H-BC for Cr(Ⅵ)involved electrostatic attraction and redox reactions.

关 键 词：酒糟生物炭 改性 吸附 Cr(Ⅵ) 

分 类 号：X703[环境科学与工程—环境工程]