Preparation of Tymycin waste salt activated carbon and its adsorption performance for EDTA-Pb(Ⅱ)

Abstract

The organic ligands in industrial wastewater combine with heavy metal ions to form complexed heavy metals. The emission of complexed heavy metals will lead to serious environmental problems and human health problems. The waste salt activated carbon(WSAC) was prepared by pyrolytic carbonization and used to remove EDTA-Pb(Ⅱ) from simulated wastewater. The properties of WSAC were characterized by SEM and BET. Based on static adsorption experiments, the effects of initial pH of solution and coexisting ions on the adsorption behavior of EDTA-Pb(Ⅱ) by WSAC were studied. Adsorption kinetics and isotherm simulation, FTIR, TOC and Zeta potential were used to explore the adsorption mechanism. The results showed that the adsorption process of EDTA-Pb(Ⅱ) by WSAC was in line with the pseudo-first-order kinetics and Langmuir model, The adsorption rate was dominated by a physical process and was a homogeneous adsorption in a molecular layer. With the increase of pH, the adsorption effect of WSAC on EDTA-Pb(Ⅱ) decreased. The addition of coexisting anions could compete with EDTA-Pb(Ⅱ) for adsorption sites and inhibited the adsorption. The mechanism of adsorption of EDTA-Pb(Ⅱ) by WSAC was mainly the synergistic effect of pore filling and electrostatic adsorption. In this paper, WSAC was used to adsorb EDTA-Pb(Ⅱ) in industrial wastewater, which provided a way for the resource utilization of taymycin waste salt,and also provided a method for the removal of EDTA-Pb(Ⅱ) in industrial wastewater.

Keywords

• industrial wastewater
• complex heavy metal
• edta-pb(ⅱ)
• taymycin waste salt
• adsorption