[신간의 별자리x] 우리/미술, 그리고 ‘슬픔의 박물관’

In this review, resources of nickel and status of different processes/technologies in vogue or being developed for extraction of nickel and associated metals from both primary and secondary resourc...

Advanced Review on Extraction of Nickel from Primary and Secondary Sources

Extraction of nickel and cobalt from a laterite ore using the carbothermic reduction roasting-ammoniacal leaching process

Highly selective separation of vanadium over iron from stone coal by oxalic acid leaching

Selective leaching of nickel and cobalt from limonitic laterite using phosphoric acid: An alternative for value-added processing of laterite

Comparison of effectiveness of citric acid and other acids in leaching of low-grade Indonesian saprolitic ores

Kinetics on roasting reduction of limonitic laterite ore using coconut-charcoal and anthracite reductants

The kinetics of leaching of a saprolitic ore from Indonesia by citric acid solution under atmospheric pressure was investigated. An examination of the effects of leaching temperature, citric acid concentration, pulp density and ore particle size on the dissolution rate ofnickel found that they all had significant influence on the rate. The highest nickel recovery (95.6 percent) was achieved under the leaching conditions of ore particle size of 212–355 microns, citric acid concentration of 1 M, leaching time of 15 days, pulp density of 20 weight/volume percent, leaching temperature of 40°C and shaker speed of 200 rpm. The shrinking core model was found to be appropriate for describing the leaching kinetics of this ore in citric acid solutions at atmospheric pressure. The experimental data were well interpreted by this model with rate ofreaction controlled by diffusion through the solid product layer. Using the Arrhenius expression, the apparent activation energy for nickel dissolution was evaluated as 12.38 kJ/mol. Finally, on the basis of the shrinking core model, a proposed empirical kinetic model for the leaching of nickel from this Indonesian saprolitic ore was expressed as a mathematical model, which was verified as consistent with the obsenved experimental results.

Kinetics of nickel extraction from Indonesian saprolitic ore by citric acid leaching under atmospheric pressure

Comparison of atmospheric citric acid leaching kinetics of nickel from different Indonesian saprolitic ores

The kinetics study has an essential role in the scale-up process because it illustrates the real phenomena of a process. This study aims to develop a mathematical model that can explain the mechanism of the leaching process of laterite ore using a low concentration of the citric acid solution and evaluate that model using the experimental data. As a raw material, this process used powder-shaped limonite laterite ores with a size of 125–150 µm. The leaching process is carried out using 0.1 M citric acid solution, F:S ratio of 1:20, and a leaching time of 2 h. The temperature parameter was varied at 303, 333, and 358 K. The experimental results showed that the higher the operating temperature, the higher the extracted nickel. The results of this experiment were used to evaluate the shrinking core kinetics model and the lumped model. The simulation results for both models show that the lumped model can provide better simulation results. Quantitatively, the percentage of errors from the shrinking core model is around 3.5 times greater than the percentage of errors from using the lumped model. This result shows that in this leaching process, the process mechanism that occurs involves the reactant diffusion step and the chemical reactions step; those steps run simultaneously.

https://www.mdpi.com/2075-163X/10/7/613/pdf

Widi Astuti

Papers

Comparison of effectiveness of citric acid and other acids in leaching of low-grade Indonesian saprolitic ores

Kinetics on roasting reduction of limonitic laterite ore using coconut-charcoal and anthracite reductants

Kinetics of nickel extraction from Indonesian saprolitic ore by citric acid leaching under atmospheric pressure

Comparison of atmospheric citric acid leaching kinetics of nickel from different Indonesian saprolitic ores

Kinetic Study in Atmospheric Pressure Organic Acid Leaching: Shrinking Core Model versus Lump Model