Eventos Anais de eventos
COBEM 2023
27th International Congress of Mechanical Engineering
Assessment of temperature and electric field effect on nickel recovery from spent catalyst via electro-leaching
Submission Author:
Carolina Mocelin Gomes Pires , PR
Co-Authors:
Lucas Bittencourt, Carolina Mocelin Gomes Pires, Haroldo Ponte
Presenter: Carolina Mocelin Gomes Pires
doi://10.26678/ABCM.COBEM2023.COB2023-2121
Abstract
Catalysts from the oils and fats hydrogenation process are a matrix composed of spent catalysts and organic materials, such as free fatty acids and vegetal oil. These wastes can become an environmental problem if they do not receive a suitable solid waste treatment. However, when disposed these materials carry within themselves some species that have economical value, such as nickel. Aiming to comply with environmental standards of waste disposal, and also to recover nickel from spent catalysts, electro-leaching arises as a feasible recovering technique. Therefore, the aim of the present work was to evaluate the synergetic effect of electric field and temperature on nickel ions from spent catalysts from the hydrogenation of oils and fats process. Four experiments were conducted, in which samples were previously calcinated at 400 °C. In experiments 1 and 2 (EL-01 and El-02), each sample was added to a solution of sulfuric acid (1.5 mol/L), remaining in the solution for 48 h. Subsequently, in the test EL-01, the mixture was submitted to the electro-leaching process for 192 h, applying an electric field of 1.0 V cm-1 at room temperature. Test EL-02 was conducted analogously to EL-01, however, the electric field was not applied. In experiments 3 and 4 (EL-03 and EL-04), samples remained in a sulfuric solution (1.5 mol/L) for 16 h. After that, in test EL-03, the mixture underwent the electro-leaching process for 48 h at 45 °C. In experiment EL-04 the mixture remained in solution, without electric field application. The results showed that test EL-03 presented the highest recovery, removing 42.5% of Ni+. On the other hand, in experiment EL-04, the Ni+ recovery was 21.1%. Tests EL-01 and EL-02 presented the lowest removal, resulting in 15.7% and 10.3% of Ni+ removal respectively. In light of these results, it was observed that the synergetic effect between temperature and electric field favored the removal of Ni+ from catalysts, enabling the species removal using a less pollutant technique than the conventional leaching process.
Keywords
electro-assisted leaching, metallic ions recovery, electromigration
