Removal of Cd(II) and Pb(II) from aqueous solutions by modified polyvinyl alcohol.

Autor: Haiyan, Jiang, Qiuxiang, Zhao, Ying, Zeng
Předmět:
Zdroj: Desalination & Water Treatment; Mar2016, Vol. 57 Issue 14, p6452-6462, 11p
Abstrakt: In this study, modified polyvinyl alcohol (PVA) was prepared and characterized by element analysis, scanning electron microscopy, Fourier transform infrared spectroscopy, and surface area and proximity analysis. The isotherms and thermodynamic parameters of the modified PVA adsorption process were estimated. The data indicate that the adsorption process is exothermic, feasible, spontaneous, and fit to the Langmuir isotherm model. The maximum adsorption capacities for Cd(II) and Pb(II) were calculated to be 1.19 and 1.48 mmol/g, respectively. Sorption was rapid, with the removal percentage higher than 98% after 10 min. Adsorption behavior mechanisms were analyzed using pseudo-first-order and pseudo-second-order models, which were highly fitted to pseudo-second-order model. This suggests the main adsorption mechanism is a chemical adsorption, involving ion exchange and valence forces through sharing or exchange of electrons between metal ions and modified PVA. The modified PVA is a good reusable sorbent, enhancing the economics of practical application for the removal of Cd(II) and Pb(II) from water and wastewater. [ABSTRACT FROM PUBLISHER]
Databáze: Complementary Index