磁性膨润土对四环素的吸附特性  

Adsorption of Tetracycline by Magnetic Bentonite

作　　者：王超[1,3] 王迎亚 陈宁华[1] 施华珍[2] 刘坤[1] 张寒冰[1,2] 童张法[2] WANG Chao WANG Ying-ya CHEN Ning-hua SHI Hua-zhen LIU Kun ZHANG Han- bing TONG Zhang-fa(School of Environment, Guangxi University, Nanning 530004, Guangxi, China Guangxi Key Laboratory of Petrochemical Resource Processing and Process Intensification Technology, School of Chemistry and Chemical Engineering, Guangxi University, Nanning 530004, Guangxi, China Xinghua Construction Group Co. , Ltd, Nanning 530028, Guangxi , China)

机构地区：[1]广西大学环境学院,广西南宁530004 [2]广西大学化学化工学院,广西石化资源加工及工程强化技术重点实验室,广西南宁530004 [3]兴华建设集团股份有限公司,广西南宁530028

出　　处：《精细化工》2017年第10期1185-1193,共9页Fine Chemicals

基　　金：国家自然科学基金(21576055,51668006);广西碳酸钙产业化工程院开放课题(TSG201501);广西石化资源加工及过程强化技术重点实验室主任课题(2016Z006)~~

摘　　要：为了有效治理废水中抗生素带来的严重污染,并解决粉状吸附剂的分离回收问题,采用微波固液相合成法原位生成磁性膨润土(Magnetic bentonite,M-Bent),并进行静态吸附实验,考察了M-Bent的投加量、抗生素溶液起始pH、金属Cu2+以及腐殖酸(Humic acid,HA)对M-Bent去除四环素(Tetracycline,TC)废水性能的影响,还对相应的吸附动力学和吸附等温模型进行拟合。结果表明:M-Bent的饱和磁化值是9.41 emu/g,能够成功实现固液分离;M-Bent具有一定的热稳定性,可以在30~700℃内保持结构的稳定;TC起始pH在3~9时M-Bent对其去除率均高达85%以上,说明M-Bent吸附TC有很宽的pH适宜范围;M-Bent在投加量为0.5 g/L时,对质量浓度为20 mg/L的TC溶液的处理效果可以达到91%的去除率;Cu2+浓度的升高会促进M-Bent对TC的吸附,使吸附效率呈现小幅的上升趋势;而HA的共存则会抑制M-Bent对TC的吸附,随着HA浓度的升高,M-Bent对TC的吸附呈现明显的下降趋势;M-Bent吸附TC的过程符合准二级动力学模型,是一个先快速吸附再缓慢达到平衡的过程;吸附等温模型的拟合结果符合Langmuir吸附模型,说明TC在M-Bent的吸附过程是单分子层吸附,吸附容量Qm为147 mg/g。To control the serious pollution caused by wastewater containing antibiotics and solve the solid-liquid separation problem of powder adsorbents,the magnetic bentonite（ M-Bent） was in situ prepared using a solid-liquid synthetic method under microwave irradiation. The dosage of M-Bent,the initial pH of solution,the co-existed substance of Cu2 ＋or humic acid（ HA） were varied step by step to investigate their influence on the removal of tetracycline（ TC） by static adsorption experiments.Moreover,the corresponding adsorption kinetics and isotherms were fitted according to the adsorption equilibrium data. The results showed that M-Bent with a saturation magnetization of 9. 41 emu/g could realize the solid-liquid separation of solution. In addition,M-Bent exhibited a certain thermal stability within 30 ~ 700 ℃. The removal rate of TC by M-Bent kept above 85% at the initial pH value from 3 to9,indicating that M-Bent displayed a high adsorption for TC in a wide range of pH. The removal rate of TC reached 91% for 20 mg/L TC solution when the dosage of M-Bent was 0. 5 g/L. The adsorption efficiency of TC slightly increased with the increase of Cu2 ＋concentration,which showed that Cu2 ＋accelerated TC adsorption on M-Bent. While the presence of HA inhibited TC adsorption on M-Bent,when HA concentration increased,the removal rate of TC displayed a declining variation trend. The kinetic data indicated that the adsorption process fitted the pseudo-second-order kinetics model,which was a fast adsorption first and then slow equilibrium process. The TC adsorption equilibrium data fitted the Langmuir model better with a Langmuir maximum adsorption capacity（ Qm） of 147 mg/g,so this adsorption was a monolayer adsorption.

关 键 词：磁性膨润土 四环素 吸附 铜 腐殖酸 水处理技术与环境保护 

分 类 号：X703[环境科学与工程—环境工程]