Phosphate Sequestration From Aqueous Solutions Using A Zeolite in The Zinc Form.

Abstract

This work evaluated the ability of a modified zeolite to adsorb phosphates in aqueous solution. The zeolite used for this study was a modified faujasite impregnated with zinc chloride (Z-Zn) on its surface. The experiments were carried out in different stages. Adsorption was performed at different pH of the solution and the zeolitized material was found to be favorable for phosphate adsorption. The adsorption kinetics occurred after 240 minutes and reach the equilbrium, determining chemisorption reactions with a fit of the particular diffusion model ( Dp ) and pseudo second order, the Langmuir model was best adjusted through the isotherms. The adsorption and desorption process occurs best in the presence of HCl, the formation of residual phosphorous in the fractionation stage evidenced that the highest percentage was bound to metals such as Fe and Al.

Computational Study of the Adsorption of Phosphates as Wastewater Pollutant Molecules on Faujasites

“…Likewise, the O-H bond distance of FAU-Y, closer to the NaH2PO4 molecule, was 1.1 Ǻ, which suggested an interaction between an O atom of the NaH2PO4 molecule and an H atom of FAU-Y. A similar computational study of H3PO4 adsorption on ZSM-5 showed analogous behavior [3,59].…”

“…Likewise, the O-H bond distance of FAU-Y, closer to the NaH 2 PO 4 molecule, was 1.1 Å, which suggested an interaction between an O atom of the NaH 2 PO 4 molecule and an H atom of FAU-Y. A similar computational study of H 3 PO 4 adsorption on ZSM-5 showed analogous behavior [3,59]. After full optimization, the O(SHDP)-H(FAU-Y) bond distance was 1.4 Ǻ, and the hydrogen atoms of the molecule were located at a distance of 2.3 Ǻ and 2.1 Ǻ, respectively.…”