Abstract

Guar gum-graft-poly(vinylacetate) (GG-g-PVA) has been synthesized and evaluated for Hg(II) removal from synthetic Hg(II) solution. The optimum performance GG-g-PVA sample (G1) was synthesized using 0.25 g guar gum, 1.0 × 10 -2 M K2S2O8, 2.3 × 10-2 M ascorbic acid, 0.46 M vinyl acetate (VA), total reaction volume 25 mL, grafting time 1 h, and reaction temperature 35±0.5 °C. G1 has been extensively characterized using FTIR, SEM, TGA, and DSC studies. pH drift experiments have shown that G1 has pHzpc of 2.8 and it was most efficient in removing Hg(II) at pH 6. The kinetic studies indicated that the removal involved chemisorption in the rate determining step and the sorption equilibrium was attained in 4 h. High Qmax (100 mg g -1 ) of the copolymer indicated its suitability as a versatile and sustainable adsorbent for exceptionally high mercury recovery.

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