摘要
以小麦秸秆为原料热解制备生物炭,分别用FeSO4/FeCl3和FeCl3对生物炭进行表面改性。表征结果显示,改性生物炭表面存在磁性颗粒和Fe—O基团,负载铁后生物炭的比表面积和总孔体积显著增大。吸附实验结果表明,改性后生物炭吸附Cr(Ⅵ)的吸附性能优于未改性生物炭,且以FeSO4/FeCl3改性的生物炭吸附性能更佳,在Cr(Ⅵ)溶液初始pH为2、初始浓度为100 mg·L^-1、温度为30℃、振荡速率为150 r·min-1、生物炭投加量为4 g·L^-1、吸附时间为48 h的条件下,FeSO4/FeCl3改性的生物炭对Cr(Ⅵ)的去除率达93.9%;负载铁生物炭对Cr(Ⅵ)的吸附符合拟二级动力学模型和Langmuir等温吸附模型。
Biochar was derived from wheat straw by pyrolysis and then modified by FeSO4/FeCl3 and FeCl3,respectively.The characterization results indicate that magnetic particles and Fe—O group are present on the surface of the modified biochar,and the specific surface area and total pore volume of the modified biochar increase significantly.The results of adsorption experiments show that the adsorption performance of Cr(Ⅵ)by modified biochar is better than that of unmodified biochar,and the biochar modified by FeSO4/FeCl3 is preferred.Under the conditions of the initial pH of the solution at 2,the initial concentration of Cr(Ⅵ)at 100 mg·L^-1,the temperature at 30℃,the oscillation rate at 150 r·min-1,the biochar dosage at 4 g·L^-1,and the adsorption time being 48 h,the removal rate of Cr(Ⅵ)by FeSO4/FeCl3 modified biochar reaches 93.9%.The adsorption of Cr(Ⅵ)by the iron modified biochar conforms with the pseudo-second-order kinetic model and the Langmuir isotherm adsorption model.
作者
康宁
毛磊
张宇
梁文懂
马毅
Kang Ning;Mao Lei;Zhang Yu;Liang Wendong;Ma Yi(College of Chemistry and Chemical Engineering, Wuhan University of Science and Technology, Wuhan 430081, China;Hubei Coal Conversion and New Carbon Materials Key Laboratory, Wuhan University of Science and Technology, Wuhan 430081, China;Shanxi Lu’an Mining (Group) Co., Ltd., Changzhi 046299, China)
出处
《武汉科技大学学报》
CAS
北大核心
2020年第3期185-193,共9页
Journal of Wuhan University of Science and Technology
基金
国家自然科学基金资助项目(51204125).
关键词
负载铁生物炭
小麦秸秆
表面改性
Cr(Ⅵ)吸附
吸附动力学
吸附性能
Fe-impregnated biochar
wheat straw
surface modification
Cr(Ⅵ)adsorption
adsorption kinetics
adsorption performance