Removal of mercury and methylene blue from aqueous solution by xanthate functionalized magnetic graphene oxide: Sorption kinetic and uptake mechanism

Limei Cui; Xiaoyao Guo; Qin Wei; Yaoguang Wang; Liang Gao; Liangguo Yan; Tao Yan; Bin Du

doi:10.1016/j.jcis.2014.10.019

Removal of mercury and methylene blue from aqueous solution by xanthate functionalized magnetic graphene oxide: Sorption kinetic and uptake mechanism

J Colloid Interface Sci. 2015 Feb 1:439:112-20. doi: 10.1016/j.jcis.2014.10.019. Epub 2014 Nov 1.

Authors

Limei Cui¹, Xiaoyao Guo¹, Qin Wei², Yaoguang Wang², Liang Gao², Liangguo Yan¹, Tao Yan¹, Bin Du³

Affiliations

¹ School of Resources and Environment, University of Jinan, Jinan 250022, China.
² Key Laboratory of Chemical Sensing & Analysis in Universities of Shandong, School of Chemistry and Chemical Engineering, University of Jinan, Jinan 250022, China.
³ School of Resources and Environment, University of Jinan, Jinan 250022, China. Electronic address: dubin61@gmail.com.

PMID: 25463182
DOI: 10.1016/j.jcis.2014.10.019

Abstract

Xanthate functionalized magnetic graphene oxide (Fe3O4-xGO) was successfully synthesized through linking xanthate groups to a kind of graphenes magnetic material (Fe3O4-GS). Fe3O4-xGO was found to be an ideal adsorbent for Hg(II) and methylene blue removal with a higher adsorption capacity. The synthesized adsorbent was characterized by SEM, TEM, FTIR, XRD, and BET respectively. Fe3O4-xGO can be simply recovered from water with magnetic separation at low magnetic field within only 1min. The adsorption capacity was found to be 118.55mg g(-1) for Hg(2+) (contact time for 180min, pH at 7 and temperature at 25°C) and 526.32mg g(-1) for methylene blue (contact time for 120min, pH at 5.5 and temperature at 25°C), respectively. Kinetic data showed good correlation with pseudo-second-order equation and the Langmuir model was found to fit for the isotherm data, which showed the contaminant sorption was accomplished mainly via chelation or ion exchange. The results of thermodynamic studies (ΔG<0, ΔH>0, ΔS>0) illustrate that the adsorption process was endothermic and spontaneous in nature. The experimental results suggest that Fe3O4-xGO has the potential applications in the environmental management.

Keywords: Adsorption; Fe(3)O(4)-xGO; Mercury; Methylene blue.