A novel adsorbent, called dithiocarboxyl cornstalk (DTCS), was developed, and the effects of various parameters on the adsorption performance for Cd(II) with DTCS were investigated in this work. The results suggested that DTCS presented the efficient removal capacity for Cd(II) when the pH values, adsorption temperature, and oscillation rate were 3.0 to 6.0, 313 K, and 150 rpm, respectively. The adsorption kinetic data were more agreed with pseudo-second-order kinetic model, and the isotherm data could be characterized by Freundlich model. The thermodynamic data indicated the adsorption process was endothermic and spontaneous. The FTIR and SEM confirmed the chemisorption between Cd(II) and DTCS. Furthermore, to eliminate the secondary pollution, the waste filtrate generated in the preparation of DTCS was employed to remove Cd(II) through flocculation experiments. The results showed that the waste filtrate is a potential flocculant for the treatment of wastewater containing Cd(II).
Keywords: Cadmium removal; adsorption; cornstalk; dithiocarboxylation; flocculation.