Development of biodegradable porous starch hydrogels containing modified nanocellulose or nanoclays for the removal and recovery of metals in contaminated water

• Grant number: 22/11133-0
• Support Opportunities: Scholarships in Brazil - Post-Doctorate
• Effective date (Start): October 01, 2022
• Effective date (End): September 30, 2024
• Field of knowledge: Engineering - Materials and Metallurgical Engineering - Nonmetallic Materials
• Principal Investigator: Derval dos Santos Rosa
• Grantee: Talles Barcelos da Costa
• Host Institution: Centro de Engenharia, Modelagem e Ciências Sociais Aplicadas (CECS). Universidade Federal do ABC (UFABC). Ministério da Educação (Brasil). Santo André , SP, Brazil
• Associated research grant: 20/13703-3 - Environmentally friendly porous materials for the recovery and revaluation of metals reclaimed from contaminated water, AP.TEM

Abstract

Currently the world faces difficulties related to the quantity and quality of water due to industrial expansion, population growth, and urbanization intensification. Toxic metals are widely used in various industrial activities and are often found in wastewater. The presence of these metals in water resources is related to risks to human health and the environment. The recovery and revaluation of metals present in contaminated water is essential for cleaner production in a circular economy perspective. Adsorption is considered an alternative technology with high potential for removal and recovery of these elements at low concentrations. The application of nanostructured adsorbents, such as biodegradable porous hydrogels, can increase the adsorption capacity of these metals. In order to improve the effect of polymeric hydrogels and optimize their properties, low-cost and ecologically correct methodologies have been studied, analyzed by Life Cycle Assessment (LCA), and applicable on a large scale. This project proposes the development of biodegradable nanocomposite hydrogels of starch containing nanocellulose or nanoclays modified for adsorption and desorption of metallic contaminants (Cd2+, Cr6+, Cu2+, Mn2+, Ni2+, Zn2+) in aqueous medium. For the synthesis of nanocomposites, we intend to use an innovative methodology to evaluate the effect of crosslinking agent concentrations, process parameters (preparation time, temperature, crosslinking time), and the influence of different nanoparticles (cellulose and clay) without and with modification. Nanoparticles and hydrogel systems will be investigated regarding their chemical composition, mechanical properties, porosity, adsorption and desorption capacity of metallic contaminants. The biodegradation and ecotoxicity of hydrogels will be characterized after use/reuse cycles to describe the biodegradation mechanism and the influence of residual metals throughout the decomposition process. Thus, this project aims to develop modified porous hydrogels with high capacity for treatment and metals recovery from contaminated water, as well as the reuse of these nanocomposites developed post-consumer for applications in agricultural soil, mitigating the environmental impacts associated with the disposal of these materials.