Removal of fluoride from wastewater solution using Ce-AlOOH with oxalic acid as modification

Wen Tao; Hong Zhong; Xiangbo Pan; Peng Wang; Haiying Wang; Lei Huang

doi:10.1016/j.jhazmat.2019.121373

Removal of fluoride from wastewater solution using Ce-AlOOH with oxalic acid as modification

J Hazard Mater. 2020 Feb 15:384:121373. doi: 10.1016/j.jhazmat.2019.121373. Epub 2019 Oct 1.

Authors

Wen Tao¹, Hong Zhong¹, Xiangbo Pan², Peng Wang³, Haiying Wang⁴, Lei Huang⁵

Affiliations

¹ College of Chemistry and Chemical Engineering, Hunan Provincial Key Laboratory of Efficient and Clean Utilization of Manganese Resources, Central South University, Changsha 410083, Hunan, China.
² Changsha neptunus pharmaceutical co, ltd, China.
³ School of Metallurgy and Environment, Central South University, Changsha 410083, China.
⁴ School of Metallurgy and Environment, Central South University, Changsha 410083, China. Electronic address: haiyw25@163.com.
⁵ School of Metallurgy and Environment, Central South University, Changsha 410083, China. Electronic address: znhuanglei@foxmail.com.

PMID: 31607582
DOI: 10.1016/j.jhazmat.2019.121373

Abstract

In this paper, Ce-AlOOH were investigated to develop as an adsorbent for removing fluoride. Oxalic acid was selected as an effectively modified reagent to improve the performance of adsorption. Cerium existed in the form of CeO₂ and kept good stability during the adsorption process through XRD, TEM, BET, Raman, and Infrared spectra. The adsorption capacity could be improved with the addition of cerium (62.8 mg/g). Specially, the oxalic acid modification significantly promoted the adsorption capacity to 90 mg/g. There adsorption isotherm and kinetics were estimated independently. These adsorption behaviors were in accordance with the Freundlich model and pseudo-second-order model, indicating that chemisorption was the rate-determining step. the obtained adsorbents all exhibited good recycling performance using oxalic acid as the regeneration reagent. The species of tetravalent cerium was the important adsorption sites. The mechanism was carefully explored by XPS analysis. The fluoride adsorption process can be ascribed to the combined effect of the electrostatic action, surface coordination, and ion exchange between M-OH and F^-. Furthermore, modification of oxalic acid exhibited a new easier way to quickly increase M-OH content, which contributed to the dominated adsorption sites.

Keywords: Adsorption; AlOOH; Cerium oxide; Fluoride removal; Oxalic acid.

Publication types

Research Support, Non-U.S. Gov't