Synthesis and evaluation of thiosemicarbazide functionalized corn bract for selective and efficient adsorption of Au(III) from aqueous solutions

In this study, corn bract was modified with thiosemicarbazide (TSC-CCB) and used to selectively adsorb Au(III) from aqueous solutions. FT-IR spectroscopy, Scanning electron microscope and X-ray photoelectron spectroscopy were used to characterize TSC-CCB and investigate the adsorption mechanism. The results suggested that the maximum adsorption amount of Au(III) was 1470.22 mg/g at 25 degrees C with pH of 6.0. The adsorption isotherm and kinetic data were matched adequately with Langmuir model and pseudo-second-order model, respectively. Meanwhile, TSC-CCB presented a good selectivity for Au(III) from the competitive ions. The ion exchange and chelation between Au(III) and S/N groups played an important role in the enhancement of the adsorption capacity. The regeneration experiments suggested that the TSC-CCB retained high adsorption efficiency after three cycles. TSC-CCB was a promising adsorbent for recovery Au(III) from wastewater in the view of sustainability. (C) 2018 Elsevier B.V. All rights reserved.