Study on the preparation of composite adsorbent with titanium-containing blast furnace slag and chromium adsorption performance
Cr(Ⅵ)is a harmful pollutant that not only pollutes the water environment but also causes harm to humans.In this paper,a new composite adsorbent(GLZ-jcz/CS)was prepared for the removal of Cr(Ⅵ)from wastewater,using industrial solid waste containing titanium blast furnace slag as raw material,and the leached slag matrix was obtained by acid leaching and modified by chitosan.The effects of adsorption temperature,pH of wastewater,adsorbent dosage,initial concentration of Cr(Ⅵ)and adsorption time on the adsorption performance of Cr(Ⅵ)were studied.The optimal experimental conditions were determined using the Cr(Ⅵ)adsorption rate as the evaluation index,and the regeneration performance of GLZ-jcz/CS composite adsorbent was investigated.The GLZ-jcz/CS composite adsorbent was characterized by SEM,FTIR,XPS and BET,combined with adsorption kinetic model and adsorption isotherm model analysis to determine the adsorption mechanism.The experimental results showed that the adsorption rate reached 99.8%and the adsorption capacity could reach 67mg/g when the adsorption temperature was 70℃,the pH of wastewater was 4,the amount of adsorbent was 0.13g,the initial concentration of Cr(Ⅵ)was 50mg/L and the adsorption time was 2h.The GLZ-jcz/CS composite adsorbent can still reach over 96%adsorption after six elutions,and the adsorption model was compounded with the proposed secondary kinetic model and the Langmuir adsorption isotherm model.