摘要
为了回收再利用工业废弃物煤渣,本文利用负载法制备了氯化镁改性的煤渣除氟吸附剂(MgMC),通过扫描电镜(SEM)和粉末X射线衍射(PXRD)对其结构进行了表征,考察了吸附剂投加量和溶液pH对Mg MC吸附F^-性能的影响.与未改性煤渣和氯化钙改性煤渣除氟吸附剂(CaMC)相比,Mg MC对F^-有更好的去除效果.研究结构表明,当选择F^-溶液的初始浓度为30 mg·L^(-1)和吸附剂投加量为30 g·L^(-1)时,在pH=2~11的范围内Mg MC吸附F^-的效率均达到90%以上.在最佳条件下,当F^-的浓度较低时,F^-出水浓度达到了国家饮用水标准;当F^-的浓度较高时,F^-出水浓度达到了国家废水排放的标准.在不同浓度下,MgMC对F^-的吸附过程可以用表观二级动力学模型和Langmuir吸附等温方程来描述,在303 K时MgMC的吸附量达到最大值63.694 mg·g^(-1).
To improve industrial waste cinder adsorption capacity for fluoride, magnesium chloride modified cinder （MgMC） was synthesized by load method and characterized by SEM and PXRD. The results show that MgMC has higher defluoridation efficiency than cinder. Defluoridation efficiencies are above 90 % in pH range of 2 - 11 with the dosage of 30 g·L^-1 and the initial fluoride concentration of 30 mg·L^-1. Under the best opera-tional conditions, F^- concentrations of effluent can be up to national standard of drinking water at lower concen- tration, while F^- concentrations of effluent meet state standard for wastewater discharge at higher concentration. The adsorption kinetics at different fluoride concentrations follows the pseudo second-order kinetics nicely. The sorption process of fluoride onto MgMC is subjected to Langmuir isotherm, and the maximum defluoridation capacity of MgMC is 63. 694 mg·L^-1 at 303 K. In addition, thermodynamic parameters show adsorption of fluoride onto MgMC is a spontaneous and endothermic process.
作者
李向霞
王丽娟
沈俊菊
LI Xiang-xia WANG Li-juan SHEN Jun-ju(College of Chemistry and Materials Science, Shanxi Normal University, Linfen 041000, Shanxi, China)
出处
《山西师范大学学报（自然科学版）》
2016年第3期47-52,共6页
Journal of Shanxi Normal University(Natural Science Edition)
基金
山西省高校高新技术产业化项目(20110016)
关键词
改性煤渣
氯化镁
除氟
modified cinder
magnesium chloride
defluoridation
