The effect of NaCl addition and biomass palm kernel shell charcoal with different ratio on pyrometallurgical process of a wasted ferronickel slag

Abstract

In nickel ore smelting, ferronickel slags is one of the outcome from the process. Further utilization of valuable elements in it needs to be processed. In this research, further utilization of the valuable elements is done by pyrometallurgy process where palm kernel shell charcoal was used as reductor. Palm kernel shell charcoal is a biomass fuel, with a very low ash and sulphur contents, therefore it will not release a harmful gases and greenhouse gases into the environment. The pyrometallurgy process is done by heating the ferronickel slag size #200 mesh using furnace carbolite with the mass ratio of the palm kernel shell are 5%, 10%, 15%, 20% respectively and the addition of sodium chloride 10% with operating temperature at 1000°C for 60 min. The result of the reduction then follows with magnetic separation. The result was tested with AAS and XRD, and it showed the content of nickel and iron are increased up tp the optimum point and then decreased, as the ratio of palm kernel shell charcoal increased. Based on the result, optimal parameter for nickel content is obtained by 15% palm kernel shell charcoal at 1000°C for 60 min where the concentrate is 0.153%. Based on the XRD result, it shows that with the use of palm kernel shell charcoal with the addition of NaCl can help to break the complex compounds that made the enhancement of valueable metals are hard in the first place, and can also reduce the oxide compound that is contained on the nickel slag.