摘要
为了去除水中高毒性的重铬酸根(Cr2O7^2-),采用Zr4+与2,2′-联喹啉-4,4′-二甲酸(H2L)在溶剂热条件下反应,合成了一种Zr-有机骨架材料,对水中的Cr2O7^2-进行物理吸附。分别使用X射线衍射、傅里叶红外光谱、扫描电镜、热重分析对Zr-MOF进行结晶性、化学官能团、表面形貌、热稳定性进行分析。研究Zr-MOF的用量、Cr2O7^2-的初始质量浓度和吸附温度对吸附效能的影响。结果表明,所合成的目标产物Zr-MOF结晶性良好,呈多面体,热稳定性优异。Zr-MOF对Cr2O7^2-的吸附量随着吸附剂用量的增大而减小,随着Cr2O7^2-初始浓度的升高而升高,随着环境温度的升高而降低。当Zr-MOF的用量为15mg,Cr2O7^2-的初始浓度为20mg/L,吸附温度为25℃时,吸附效果较好。Zr-MOF对水溶液中Cr2O7^2-的物理吸附过程符合准二级动力学模型,其吸附行为符合Freundlich等温吸附方程。
In order to remove highly toxic dichromate (Cr 2O 7^2-) from water, a Zr-organic framework material was synthesized by employing Zr 4+ with 2,2′-biquinoline-4,4′-dicarboxylic acid (H 2L) under solvothermal reactions to remove Cr 2O 7^2- through physical adsorption.Crystallinity, chemical functional group, surface morphology, and thermal stability of Zr-MOF were analyzed by X-ray diffraction, fourier transform infrared spectroscopy, scanning electron microscopy, and thermogravimetric analysis, respectively.The effects of the amount of Zr-MOF, the initial mass concentration of Cr 2O 7^2- and the adsorption temperature on the adsorption efficiency were investigated.The results show that the target product Zr-MOF synthesized has good crystallinity, polyhedron, and excellent thermal stability.The adsorption amount of Zr-MOF towards Cr 2O 7^2- would decrease as the amount of adsorbent grows and increase as the initial concentration of Cr 2O 7^2- intensifies, and decrease as the ambient temperature rises.When the amount of Zr-MOF is 15 mg, the initial concentration of Cr 2O 7^2- is 20 mg/L, the adsorption temperature is 25 ℃,and thus the adsorption effect is bettter.Moreover, the physical adsorption process of Zr-MOF towards Cr 2O 7^2- in aqueous solution is more consistent with the quasi-secondary kinetic model, and its adsorption behavior is more in line with the Freundlich isotherm adsorption equation.
作者
哈尔祺
樊增禄
李庆
李世奇
王雅
HA Erqi;FAN Zenglu;LI Qing;LI Shiqi;WANG Ya(School of Textile Science and Engineering,Xi′an Polytechnic University,Xi′an 710048,China;School of Environmental and Chemical Engineering,Xi′an Polytechnic University,Xi′an 710048,China)
出处
《纺织高校基础科学学报》
CAS
2019年第3期237-243,共7页
Basic Sciences Journal of Textile Universities
基金
陕西省科技计划资助项目(2019GY-163)
西安市科技创新引导项目(201805030YD8CG14(18))
