Properties of catalyst for iron and manganese oxidation in filter materials

Joanna Jeż-Walkowiak,Przemysław Zakrzewski,Marek M Sozański,Zbysław Dymaczewski,Malgorzata Komorowska-Kaufman

doi:10.1051/e3sconf/20185900014

Joanna Jeż-Walkowiak, Przemysław Zakrzewski + Show 3 more

Open Access

https://doi.org/10.1051/e3sconf/20185900014

Copy DOI

Abstract

The aim of this work is to determine the properties of contact layers of grain of different type of filter media in term of their suitability for catalytical manganese oxidation and auto-activation for manganese removal from groundwater. The following oxidative filtration materials were investigated: auto-activated silica sand taken from full-scale filters (oxide coated filter media), Pyrolox – manganese ore – natural material and Hydrolit – artificially activated material. As a reference two natural not chemically active materials were tested: clean silica sand and clean chalcedonite. The investigation resulted in chemical composition and microstructure parameters of catalyst contact layers of grains. The modern analytical methods were used: EDAX, Raman spectroscopy, mercury and helium porozymetry. The data indicated that catalyst from autoacivated filtration material has better chemical composition and porosity parameters in comparison to tested catalytic filtration materials, making it more suitable for adsorption and catalytic manganese oxidation.

Highlights

Traditional technology of groundwater treatment consists of aeration followed by filtration
The crystalline structure of the catalytic contact layer in the manganese removal zone as well as silica sand beds were examined using the method of X-ray powder diffractometry (XRD)
The EDAX results (Table 2) indicate, that: - silica sand and chalcedonite are chemically homogenous, mostly consisting of SiO2, - catalyser of iron removal zone consists of iron

Summary

Introduction

Traditional technology of groundwater treatment consists of aeration followed by filtration. The iron and manganese removal occurs due to heterogenic and autocatalytic oxidation in catalytic-oxidative filtration beds. The catalyser is manganese dioxide – the product of Mn(II) oxidation. Most common filtration material is silica sand. Clean fresh silica sand has no catalytic properties becoming an auto-activated material after covering grains with manganese oxides. This permanent oxides contact layer may be created with no chemical dosage [1,2]. The rippening of filtration material is often supported with biological oxidation process [3,4,5,6]

Objectives

Methods

Results

Conclusion