Waste Brick Dust as Potential Sorbent of Lead and Cesium from Contaminated Water.

Barbora Doušová,Martina Urbanová,Miloslav Lhotka,Jiří Brus,Libor Kobera,David Koloušek,Martin Keppert

doi:10.3390/ma12101647

Abstract

Adsorption properties of waste brick dust (WBD) were studied by the removing of PbII and CsI from an aqueous system. For adsorption experiments, 0.1 M and 0.5 M aqueous solutions of Cs+ and Pb2+ and two WBD (Libochovice—LB, and Tyn nad Vltavou—TN) in the fraction below 125 µm were used. The structural and surface properties of WBD were characterized by X-ray diffraction (XRD) in combination with solid-state nuclear magnetic resonance (NMR), supplemented by scanning electron microscopy (SEM), specific surface area (SBET), total pore volume and zero point of charge (pHZPC). LB was a more amorphous material showing a better adsorption condition than that of TN. The adsorption process indicated better results for Pb2+, due to the inner-sphere surface complexation in all Pb2+ systems, supported by the formation of insoluble Pb(OH)2 precipitation on the sorbent surface. A weak adsorption of Cs+ on WBD corresponded to the non-Langmuir adsorption run followed by the outer-sphere surface complexation. The leachability of Pb2+ from saturated WBDs varied from 0.001% to 0.3%, while in the case of Cs+, 4% to 12% of the initial amount was leached. Both LB and TN met the standards for PbII adsorption, yet completely failed for any CsI removal from water systems.

Highlights

The contamination of waters and soils by toxic carcinogens and radioactive nuclides is a pressing environmental problem
In terms of waste brick dust (WBD) with the average pHZPC of 5, a higher pH of adsorption has been essential for selective removal of Pb2+ /Cs+
The adsorption selectivity of WDBs to Pb(II) and Cs(I) was initially affected by the structural properties and morphology of WBDs being tested as Pb2+ /Cs+ adsorbents

Summary

Introduction

The contamination of waters and soils by toxic carcinogens and radioactive nuclides is a pressing environmental problem. There is particular concern for accumulative poisonous effects in local environments. Lead (Pb) is one such element that has well known chronic influence on the central nervous system, where it replaces the residing zinc in neurons. It is generally believed that the anthropogenic sources of Pb are limited to the use of tetraethyl lead, other Pb origins, such as battery manufacturers, lead smelters and ammunition industries are all major Pb polluters of the environment [1,2]. Cesium as 137 Cs is an important source of radioactivity from nuclear waste, as it is the major radionuclide of spent nuclear fuel [3]. Due to nuclear accidents over the last decades (e.g., Fukushima in 2011, Chernobyl in 1986), 137 Cs has infiltrated soils and groundwater and even further into the biosphere thanks

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