Aplicação de planejamentos experimentais multivariados à lixiviação de cobre presente em placas de circuito impresso.

The volume of Waste Electrical and Electronic Equipment (WEEE) produced worldwide in 2018 was 50 million tons. Around 2% of this waste is Printed Circuit Boards (PCB), which contain noble and base metals, with copper being the most abundant element (10-20%). Additionally, toxic metals as lead, cadmium and mercury are present, which can cause harmful effects to the environment and human health. Therefore, PCB recycling is an important initiative, not only due to environmental issues but also considering the economic aspects. This research aimed to optimize the variables (i) pulp density, (ii) concentration of ferric chloride hexahydrate, (iii) concentration of hydrochloric acid and (iv) time that influence the copper leaching process contained in PCB of computers through a multivariate experimental design. The leaching assays were carried out in batches, in a shaker, under stirring of 150min-1 and temperature of 25±1°C. The optimum conditions for copper leaching were pulp density of 120g.L-1, concentration of ferric chloride hexahydrate and hydrochloric acid of 1mol.L-1, and time of 40 minutes. For the optimized condition, the percentage of copper leaching was 96.22±1.20%. [ABSTRACT FROM AUTHOR]