Nickel (ii) Ion adsorption by native and treated pea pods

Abstract

The paper describes a study on static Ni2+ ions adsorption by native and treated shells of pea pods (Pisum sativum). Pea pod shells were treated with 1-3% sulfuric acid or sodium hydroxide solutions. Adsorption isotherms were constructed and calculated according to the Langmuir, Freundlich, Tyomkin, and Dubinin-Radushkevich models. It was found that all constructed isotherms were most accurately described by the Freundlich model. It was determined that the highest sorption capacity for Ni2+ ions was shown by 3% sulfuric acid solution-treated pea pods. The paper also describes a study of the kinetics of Ni2+ ion adsorption by native and treated pea pod shells under static conditions. It was determined that the main mechanism of the process is mixed diffusion. The calculated thermodynamic parameters indicate physical adsorption.