摘要
采用原位生长法在磁性壳聚糖硅藻土(M-CS-DE)表面生长ZIF-7制备新型复合材料,用于吸附水中重金属Cr(Ⅵ)。首先,采用磁性壳聚糖对硅藻土进行磁改性,然后将ZIF-7原位生长到改性后的硅藻土上,成功制备新型复合材料(M-CS-DE/ZIF-7),并采用SEM、FT-IR、XRD等手段对其进行表征分析。通过研究Cr(Ⅵ)溶液的初始浓度、吸附剂用量、吸附时间、吸附温度和溶液酸碱度等因素对新型复合材料吸附容量的影响,优化了该材料对Cr(Ⅵ)的吸附条件。吸附实验还表明ZIF-7、M-CS-DE/ZIF-7均符合准二级动力学模型,表明吸附类型主要为化学吸附。通过Langmuir拟合获得ZIF-7和M-CS-DE/ZIF-7对水中Cr(Ⅵ)的最大吸附量分别为6.49和27.38mg·g^(-1)。因此,M-CS-DE修饰的ZIF-7比ZIF-7具有更好的吸附性能,是一种颇具潜力的新型吸附剂,可用于吸附去除水中的Cr(Ⅵ)。
ZIF-7 was grown on the surface of magnetic chitosan diatomite(M-CS-DE)by insitu growth method to prepare a new composite for the adsorption of heavy metal Cr(VI)in water.Firstly,diatomite was magnetically modified by magnetic chitosan,and then ZIF-7 was grown insitu on the modified diatomite.A new composite(M-CS-DE/ZIF-7)was successfully prepared and characterized by SEM,FT-IR and XRD.By studying the effects of initial concentration of Cr(VI)solution,amount of adsorbent,adsorption time,adsorption temperature and pH of solution on the adsorption capacity of the new composite,the adsorption conditions of Cr(VI)were optimized.The adsorption experiment also showed that ZIF-7and M-CS-DE/ZIF-7 all accorded with the pseudo second-order kinetic model,indicating that the adsorption type was mainly chemical adsorption.The maximum adsorption capacities of ZIF-7 and M-CS-DE/ZIF-7 for Cr(VI)in water were 6.49 and 27.38 mg·g^(-1),respectively.Therefore,M-CS-DE modified ZIF-7 had better adsorption performance than ZIF-7.It was a pote ntial new adsorbent for the adsorption and removal of Cr(VI)in water.
作者
李艳君
肖新峰
李娜
凌菲
高宇
李琳
薛建良
LI Yan-jun;XIAO Xin-feng;LI Na;LING Fei;GAO Yu;LI Lin;XUE Jian-liang(School of Safety and Environmental Engineering,Shandong University of Science and Technology,Qingdao 266590,China)
出处
《化学研究与应用》
CAS
CSCD
北大核心
2022年第5期1054-1060,共7页
Chemical Research and Application
