LI Bin1, ZHAO Ming-xing1, DAI Yu-bo2, WU Xi-chen1
(1. Department of Chemistry, Huzhou University, Huzhou 313000, China;
2.Huzhou Shengtelong Metal Products Co.,Ltd., Huzhou 313011, China)
Abstract: The tailings of bentonite purification mainly contain quartz, clinochlore, and muscovite. The ceramsites, prepared using bentonite tailing as main materials, were analyzed and tested by using XRD, IR, and SEM for studying the effect of structural changes by sintering process, the influence of Cr(VI) ion adsorption effects by variations of different parameters, such as composition?, sintering temperature, pH value, initial Cr(VI) concentration, adsorption time and temperature, and for discussing the related kinetic and thermodynamic variation. The results show that there is little effects on the adsorption of Cr(VI) ions by variation of sintering temperatures. The most appropriate sintering temperature is 1000℃. The ceramsite has main crystalline phases of quartz and wollastonite with the heterogeneous porous structure at surface. The optimum Cr(VI) ion adsorption (adsorption rate of 96.33%) by the ceramsite has been reached with the ceramsite dosage of 1g, the adsorption time of 12h, the pH value of 1, and the Cr(VI) ions concentration of 100 mg/L. The adsorption is well governed by the pseudo-second-order kinetics with mono molecular layer. The thermodynamic data show that the adsorption of Cr(VI) ions is a spontaneous endothermic reaction.
Keywords: ceramsite; bentonite tailing; adsorption; Cr(VI) ion
ACTA MINERALOGICA SINICA Vol. 39, No.2, 2019, page 211-218
