Application of cryptocrystalline magnesite-bentonite clay hybrid for defluoridation of underground water resources: implication for point of use treatment

Journal of Water Reuse and Desalination

Masindi, V.¹ 

[1]CSIR (Council of Scientific and Industrial Research), Built Environment, Hydraulic and Infrastructure Engineering, P.O. Box 395, Pretoria, 0001, South Africa and Department of Environmental Sciences, School of Agriculture and Environmental Sciences, University of South Africa (UNISA), P.O. Box 392, Florida, 1710, South Africa

关键词: adsorption;    bentonite clay;    cryptocrystalline magnesite;    defluoridation;    fluoride;    magnesite-bentonite composite;   

DOI  :  10.2166/wrd.2016.055

学科分类：工程和技术（综合）

来源: IWA Publishing

【 摘 要 】

A new synthesis method was established to fabricate a nanocomposite material comprising of cryptocrystalline magnesite and bentonite clay that has high adsorption capacity for ionic pollutants. To synthesize the composite at 1:1 weight (g): weight (g) ratio, a vibratory ball mill was used. Batch adsorption experiments were carried out to determine optimum conditions for fluoride adsorption. Parameters optimized included: time, dosage, concentration and pH. Optimum conditions for defluoridation were found to be 30 min of agitation, 0.5 g of dosage, 0.5:100 solid to liquid (S/L) ratios and 25 mg L−1 of initial fluoride ions. Fluoride removal was independent of pH. The adsorption kinetics and isotherms were well fitted by pseudo-second-order and Langmuir models, respectively, indicating chemical and monolayer adsorption. Findings illustrated that the newly synthesized adsorbent was a promising adsorbent for the environmental pollution clean-up of excess fluoride in underground water and it can be used as a point source treatment technology in rural areas of South Africa and other developing countries.

【 授权许可】

CC BY-NC-ND