Per: thamiris auxiliadora gonçalves martins (Departamento de Engenharia Química, Escola Politécnica da Universidade de São Paulo), Isabela Falconi Brandolis Alves (Departamento de Engenharia Química, Escola Politécnica da Universidade de São Paulo), Viviane Tavares de Moraes (Instituto Mauá de Tecnologia, São Caetano do Sul), Marcela dos Passos Gallluzzi Baltazar (DEPARTAMENTO DE ENGENHARIA QUÍMICA, ESCOLA POLITÉCNICA DA UNIVERSIDADE DE SÃO PAULO), Jorge Alberto Soares Tenório (DEPARTAMENTO DE ENGENHARIA QUÍMICA, ESCOLA POLITÉCNICA DA UNIVERSIDADE DE SÃO PAULO), Denise Crocce Romano Espinosa (DEPARTAMENTO DE ENGENHARIA QUÍMICA, ESCOLA POLITÉCNICA DA UNIVERSIDADE DE SÃO PAULO)
Abstract:
Reverse flotation process is a method used for remove impurities from the most abundant iron ore; the itabirite. In this process, amines surfactant are used which may prevent the reuse of water in processes. The Fenton oxidative processes and the synthesis of nanoparticles are highlighted in catalysts application and in organic substances degradation. This study performed the synthesis of copper nanoparticles (CuNPs) to employ them as catalysts of the modified Fenton reaction to degrade an amine surfactant used in reverse flotation and compared with the classic Fenton (Fe2+) reaction. CuNPs were synthesized by chemical reduction, pH 11 with copper sulfate and ascorbic acid. They were characterized by UV-Vis, DRX and DLS and Zeta potential. The nanoparticles had diameters of 125.00 to 17.22nm and stability during 50 days. The tests were prepared with 180mg/L of amine and 1890mg/L of H2O2 in 150 minutes. The degradation was assessed by UV-Vis and FT IR. The results showed that CuNPs degraded 84% of the surfactant while Fe2+ reached 89%. In this way, both processes can be used for surfactant degradation, although the CuNPs method is easier to operate at neutral pH.
