Application of graphene as a sorbent for the preconcentration and determination of trace amounts of mercury in water samples by hydride generation atomic fluorescence spectrometry

The potential of graphene as a solid-phase extraction adsorbent for the separation and preconcentration of mercury (hg) was investigated. hg2+ was found to be quantitatively adsorbed onto graphene within ph 6.0-8.0,and then completely eluted with 4.0 ml of nitric acid/methanol (1:1,v/v) solution at a flow rate of 2.0 ml min-1. a new method using a microcolumn packed with graphene as a sorbent was developed for the preconcentration of trace amount of hg2+ prior to its determination by hydride generation atomic fluorescence spectrometry. under the optimum experimental conditions,the detection limit of this method for hg2+ was 5.0 ng l-1,with an enrichment factor of 15.0,and the relative standard deviation was 3.5% at the 1.0 μg l-1 hg2+ level. the method was then applied for the determination of trace amount of hg2+ in water samples with satisfactory results. © 2015,chemical society of pakistan. all rights reserved.