Adsorption Removal of Cr(VI) from Water on Surfactant-Modified Clinoptilolite

Adsorptive effects of natural clinoptilolite (NC), HDTMA-modified natural clinoptilolite (HMNC) and CPB-modified natural clinoptilolite (CMNC) were assessed for the removal of Cr(VI) from water using stirring method. Subsequently, the surface characteristics of this three materials were analyzed by XRD and IR. Selectivity series deduced from removal effect of Cr(VI) were CMNC > HMNC > NC, and the removal rates were 96.51%, 92.14% and 37.56% respectively under treatment conditions of material size fraction of -0.25+0.15 mm, clinoptilolite concentration of 30 g·L^-1, adsorption of 30 min at the initial pH6 and 25°C. By comparing the XRD pattern of CMNC, HMNC and NC, HDTMA and CPB could be found in the CMNC and HMNC respectively. IR analysis indicated that the adsorption removal of Cr(VI) from water by CMNC, HMNC did be the function of HDTMA+ in the HMNC and CP+ in the CMNC.