Heavy metals adsortion study with sodium poliacrilate (NaPA) on contaminated soils: remeadiation technics.

• Grant number: 22/13496-3
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: April 01, 2023
• End date: November 30, 2024
• Field of knowledge: Biological Sciences - Ecology - Applied Ecology
• Principal Investigator: Silvia Pierre Irazusta
• Grantee: Alana Maria Corá
• Host Institution: Faculdade de Tecnologia de Sorocaba (FATEC Sorocaba). Centro Paula Souza (CEETEPS). Secretaria de Desenvolvimento Econômico (São Paulo - Estado). Sorocaba , SP, Brazil

Abstract

The increasing contamination of the ecosystem derived from industrial activities is a problem to be solved by society and organizations. Even under state and federal laws the incorret discard of contaminated residues in water courses and soils still happens and the consequence over the years is the occurence of environmental liabilities, more frequente in industrial areas. In this study we propose a low cost method to treat heavy metal contaminated soil, using a permeable reactive barrier (PRB). A system will be made in laboratorial scale with soil collected from a ground contaminated by toxic metals. The system will have a column with three layers, one of soil contaminated with metals, one of sodium polyacrylate (NaPA) and one of the substrate prepared according to ISO 11268-1:2012 and OECD 207:1984, with adaptation by Garcia et al. (2004). For the percolation occurence of the metals presents in the superior layer to the inferior layer a controlled flux of water will be add, the system will be kept for periods of 30 to 60 days, after that the system will be disassembled and samples of the three layers will be collected in order to analyses the metal content. Furthermore, the bioindicators from the species E. andrei will be exposed to the, likely, contaminated control substrate after the period of experimentation, for 14th days, on the 7th day the earthworms will be counted and weigh in the balance and at the 14th the same process wil be repeated for final evaluation. After the experimentation period the bioindicators will be euthanized by the cold, lyophilized and metalized with Au/Pd and analysed by MEV-EDS for possible bioaccumulation for the organisms. In order to prove the efficiency of the adsoption barrier, in other words, if occured the percolation of the contaminants through the polymer, samples of the layers will be analysed for the atomic adsorption spectrometry. It is intended to describe a low-cost method capable of retaining metals from contaminated soils using a superabsorbent polymer. From this study, it is expected to contribute to the processes of remediation of industrial environmental liabilities, through the use of adsorption barriers in land used for the deposition of metallic waste, with subsequent destination of this polymer.