Development of Cellulose Aerogels for Removal of Metal Ions Present in Contaminated Water and Their Life Cycle Assessment

• Grant number: 24/23605-0
• Support Opportunities: Scholarships in Brazil - Master
• Start date: May 01, 2025
• End date: January 31, 2027
• Field of knowledge: Engineering - Materials and Metallurgical Engineering
• Principal Investigator: Derval dos Santos Rosa
• Grantee: Ana Clara Santos Brandão
• 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

Economic growth and the development of large industries bring a range of environmental damages, including soil and water contamination by potentially toxic elements (PTEs), particularly metal ions, which cause severe harm to human health and other organisms. A method for removing these ions from water involves various treatments; however, the more sophisticated ones are costly, and others leave low residual levels in the water we consume. One solution is the use of aerogels, which "capture" contaminants in their porous structures. In the search for more sustainable alternatives for aerogel production, utilizing cellulose from lignocellulosic waste emerges as a promising option, as cellulose can be extracted from residual materials like eucalyptus cutting waste, which is generally incinerated despite being rich in cellulose structures. Based on the need to find environmentally friendly means to remove water contaminants and aiming to repurpose eucalyptus waste, this study proposes a comparison-using Life Cycle Assessment (LCA)-of the development of cellulose aerogels based on different methods from the literature. Two cellulose extraction methods will be applied: the first involves alkaline treatment (sodium hydroxide and sodium hypochlorite) of the biomass followed by mechanical fiber milling; the second involves structural modification of cellulose molecules via TEMPO-mediated oxidation, followed by a faster milling process. In aerogel production, two crosslinking agents will be compared-citric acid and epichlorohydrin-for aerogel formation. The impacts of the different aerogel production processes will be quantified through LCA, and the thermal, mechanical, and sorption properties of the samples will be compared. Additionally, the effect of adding chocolate clay on the removal of Cr6+, Cd2+, Ni2+, Mn2+, Zn2+, and Cu2+ metal ions will be evaluated. The goal is to develop a sustainable, biodegradable cellulose aerogel with high efficiency in removing the studied metal ions from water.