Adsorption kinetic parameters of Fe3+ and Ni2+ ions by gyrolite

Abstract

In this work the adsorption kinetic parameters for Fe³⁺ and Ni²⁺ ions by gyrolite are presented. Additionally, the adsoption mechanism was described by using pseudo first order and pseudo second order  equations. It was determined that the adsorption capacity of gyrolite and intrusion of heavy metals ions in its structure depends on reaction time and the pH value of adsorptive. It was observed that the incorporation of Fe³⁺ ions occurs more intensive than Ni²⁺ ions. It was found that in the acidic solution the intrusion of Fe³⁺ ions into gyrolite structure proceeds by two types of chemical reaction mechanisms: substitution and addition. Meanwhile, nickel ions were participated only in substitution reaction: gyrolite-Ca⁰ + Me^x+ ↔ gyrolite-Me⁰ + Ca²⁺. It was observed that the pseudo second order model fit well for iron and nickel ions adsorption mechanism. It was estimated that the adsorption reactions are not reversible process and the crystal structure of gyrolite is stable. Moreover, synthetic adsorbent and the products of sorption were characterized by XRD, STA and FT-IR methods.

DOI: http://dx.doi.org/10.5755/j01.ms.21.1.5735