Other

Companhia Vale Do Rio Doce

Vanessa Macedo Torres

Salomão Solino Evelin

Omar Antunes Do Carmo

Marcelo Augusto Castro Lopes Da Costa

Salomao Solino Evelin

Omar Antunes Carmo

Marcelo Augusto Costa

The present invention concerns a process for the instantaneous control of the precipitation of nickel and cobalt present in a leach liquor by adjustment of the pH-value. Said leach liquor is obtained by pressurized acidic leaching of laterite ores and additionally contains aluminium, ferric and ferrous iron and chromium among others. The process comprises the following steps: precipitation of aluminium, ferric and ferrous iron, chromium etc. by increasing the pH-value by adding a suitable reagent such as lime and/or limestone, following precipitation of nickel and cobalt by further increasing the pH-value of the liquor, finally separating the precipitate from the low-content nickel and cobalt solution. The nickel and cobalt precipitate can be used for further refinement. In order to keep the process conditions constant, the steps of increasing the pH-value are controlled simultaneously.

Process for the instantaneous control of precipitation of nickel and cobalt present in the leach liquor, by adjusting the pH of the solution

Growing community of inventors

Minas Gerais, Brazil

Vanessa Macedo Torres