Effective decontamination of phosphate and ammonium utilizing novel muscovite/phillipsite composite; equilibrium investigation and realistic application

Sci Total Environ. 2019 Jun 1:667:101-111. doi: 10.1016/j.scitotenv.2019.02.362. Epub 2019 Feb 26.

Abstract

Novel muscovite/synthetic zeolitic phillipsite composite (Mu/Ph) was synthesized and inspected by different analytical techniques as a hybrid product of enhanced physicochemical properties and adsorption capacities for phosphate and ammonium. Mu/Ph adsorption systems for phosphate and ammonium were inspected considering the kinetic, equilibrium and thermodynamic studies as well as the controlling mechanisms. The kinetic behaviors of Mu/Ph for both phosphate and ammonium were remarkably described by Pseudo-second order model and the equilibration times were attained after 720 min and 480 min, respectively. The equilibrium curves for both ions were categorized as L-type isotherms which assigned mainly to systems of high affinity between the inspected adsorbents and the target dissolved ions. Additionally, the uptake results of both ions displayed slight preferences to be described by the Langmuir model. The thermodynamic studies revealed endothermic and exothermic nature for phosphate and ammonium, respectively. Moreover, the calculated parameters indicated physisorption of them by spontaneous reaction involved ion exchange processes controlled mainly by electrostatic interactions rather than ionic or covalent binding. The composite showed promising reusability properties to be applied in the reduction of phosphate and ammonium six times. The novel synthetic Mu/Ph exhibits higher capacities than numerous studied adsorbents and was applied in decontamination of phosphate and ammonium from real sewage water achieving exceptional results.

Keywords: Adsorption; Ammonium; Composite; Muscovite; Phosphate; Zeolitic phillipsite.