High efficient removal of fluoride from aqueous solution by a novel hydroxyl aluminum oxalate adsorbent

Shibiao Wu; Kaisheng Zhang; Junyong He; Xingguo Cai; Kai Chen; Yulian Li; Bai Sun; Lingtao Kong; Jinhuai Liu

doi:10.1016/j.jcis.2015.10.045

High efficient removal of fluoride from aqueous solution by a novel hydroxyl aluminum oxalate adsorbent

J Colloid Interface Sci. 2016 Feb 15:464:238-45. doi: 10.1016/j.jcis.2015.10.045. Epub 2015 Nov 14.

Authors

Shibiao Wu¹, Kaisheng Zhang², Junyong He², Xingguo Cai², Kai Chen², Yulian Li², Bai Sun³, Lingtao Kong⁴, Jinhuai Liu²

Affiliations

¹ School of Chemistry and Chemical Engineering, Anhui University, Hefei, Anhui 230039, China; Nanomaterials and Environmental Detection Laboratory, Institute of Intelligent Machines, Chinese Academy of Sciences, Hefei, Anhui 230031, China.
² Nanomaterials and Environmental Detection Laboratory, Institute of Intelligent Machines, Chinese Academy of Sciences, Hefei, Anhui 230031, China.
³ Nanomaterials and Environmental Detection Laboratory, Institute of Intelligent Machines, Chinese Academy of Sciences, Hefei, Anhui 230031, China. Electronic address: bsun@iim.ac.cn.
⁴ Nanomaterials and Environmental Detection Laboratory, Institute of Intelligent Machines, Chinese Academy of Sciences, Hefei, Anhui 230031, China. Electronic address: ltkong@iim.ac.cn.

PMID: 26624529
DOI: 10.1016/j.jcis.2015.10.045

Abstract

A novel adsorbent, hydroxyl aluminum oxalate (HAO), for the high efficient removal of fluoride from aqueous solution was successfully synthesized. The adsorbent was characterized and its performance in fluoride (F(-)) removal was evaluated for the first time. Kinetic data reveal that the F(-) adsorption is rapid in the beginning followed by a slower adsorption process; 75.9% adsorption can be achieved within 1min and only 16% additional removal occurred in the following 239min. The F(-) adsorption kinetics was well described by the pseudo second-order kinetic model. The calculated adsorption capacity of this adsorbent for F(-) by Langmuir model was 400mgg(-1) at pH 6.5, which is one of the highest capabilities of today's materials. The thermodynamic parameters calculated from the temperature-dependent isotherms indicate that the adsorption reaction of F(-) on the HAO is a spontaneous process. The FT-IR spectra of HAO before and after adsorbing F(-) show adsorption mechanism should be hydroxyl and oxalate interchange with F(-).

Keywords: Adsorption; Fluoride; Hydroxyl aluminum oxalate; Kinetics; Thermodynamics.