A Study of Using Natural Sorbent to Reduce Iron Cations from Aqueous Solutions.

Iveta Pandová,Jan Valíček,Marta Harničárová,Miroslav Rimár,Milena Kušnerová,Anton Panda

doi:10.3390/ijerph17103686

Abstract

Iron is an essential trace element, but at high doses, this element may pose a health risk. Wastewater from iron ore mining, steel production, and metal processing, among other heavy metals, also contains high concentrations of iron (Fe3+). The use of sorption on natural materials is a potential alternative to conventional methods for removing iron ions, also because of low cost. The methods presented in this article are based on the study of kinetic properties and the acquisition of adsorption isotherms, which are one of the most important characteristics of adsorption mechanisms. The course of sorption is analyzed according to the Freundlich sorption isotherm model. Isotherm parameters are evaluated using experimental results of ferric cation sorption. The results presented relate to the investigation of natural zeolite-clinoptilolite as a ferric cation sorbent, providing a measurement of the sorption kinetics as well as the observed sorption parameters of iron cations from aqueous media. The optimal time for equilibrium in the adsorption system is determined from the kinetic dependencies. The dependence of the achieved equilibrium concentration on the initial concentration of the solution was also expressed, both graphically and analytically. The new prediction model was compared with the traditional Freundlich model. Finally, adsorption isotherms tested under laboratory conditions for a practical application can be recommended for the preliminary examination of the possible technological use of natural zeolite in the wastewater treatment process.

Highlights

Contamination of soils, groundwater, surface waters, and air with hazardous toxic chemicals presents significant problems for human health and the environment
In the case of adsorption, the liquid is more firmly bound to the sorbent surface, and possible resorption would be difficult
The novelty and contribution of the presented experiments to the practice lie mainly in the fact that natural, non-toxic zeolite-clinoptilolite material was used to reduce the concentration of iron cations, which could replace synthetic cost-effective sorption materials

Summary

Introduction

Contamination of soils, groundwater, surface waters, and air with hazardous toxic chemicals presents significant problems for human health and the environment. Heavy metals are considered hazardous pollutants [1]. Their presence in wastewater comes from various industrial processes due to the development of industrial technologies. Various adsorbents, such as activated carbon [2], astragalus [3], carbon nanotubes [4,5], and a large number of bio-sorbents [6] have been used in various studies to remove pollutants, especially heavy metals from wastewater. New and efficient adsorbents with local availability in addition to economic suitability are still needed. Heavy metals are not biodegradable and tend to accumulate in living organisms

Methods

Results

Discussion

Conclusion