Tratamento de resíduos químicos contendo cobre, prata e cromo gerados nas aulas práticas do curso de licenciatura em química da ufnt.

Abstract

Educational and research institutions grapple daily with the challenging issue of chemical waste generation. These byproducts stemming from research and teaching activities vary in terms of their degree of hazardousness, necessitating appropriate treatment and/or disposal to prevent potential harm to human health and the environment. The Universidade Federal do Norte do Tocantins (UFNT) currently lacks programs for the management and treatment of chemical waste. Given the significance of addressing these waste materials generated in UFNT’s chemistry laboratories, this study aims to treat waste containing copper, silver, and chromium. To carry out the treatment of copper, silver, and chromium ion-containing waste, as well as their subsequent reuse, methodologies proposed by Dalpasquale et al. (2011) and adapted by Carlos and Marque (2022), Felisberto et al. (2008), and Armour (2005) were employed. Using reagents such as sodium hydroxide and sulfuric acid, along with procedures like filtration, heating, and calcination, a yield of 82.45% was achieved in the formation of penta-hydrated copper sulfate crystals. These crystals were utilized in practical electrochemistry classes. In the case of chromium and, silver, solid precipitates of silver chloride and chromium (III) hydroxide were obtained, significantly reducing the volume of these laboratory rejects. These approaches not only prevented environmental contamination but also facilitated the reuse of elements, contributing to cost reduction.