Evaluation of shrinking core model in leaching process of Pomalaa nickel laterite using citric acid as leachant at atmospheric conditions

2nd International Conference on Chemical Engineering (ICCE) UNPAR

Wanta, K.C.^1,2 ; Perdana, I.^1 ; Petrus, H.T.B.M.^1

Center of Advanced Material and Mineral Processing, Department of Chemical Engineering, Universitas Gadjah Mada, Jl. Grafika 2, Bulaksumur, Yogyakarta

155281, Indonesia^1

Department of Chemical Engineering, Universitas Katolik Parahyangan, Jl. Ciumbuleuit 94, Bandung

40141, Indonesia^2

关键词: Acid concentrations;    Atmospheric conditions;    Internal diffusion;    Operating temperature;    Physical phenomena;    Product diffusion;    Product molecules;    Shrinking core model;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/162/1/012018/pdf
DOI  :  10.1088/1757-899X/162/1/012018

来源: IOP

【 摘 要 】

Most of kinetics studies related to leaching process used shrinking core model to describe physical phenomena of the process. Generally, the model was developed in connection with transport and/or reaction of reactant components. In this study, commonly used internal diffusion controlled shrinking core model was evaluated for leaching process of Pomalaa nickel laterite using citric acid as leachant. Particle size was varied at 60-70, 100-120, -200 meshes, while the operating temperature was kept constant at 358 K, citric acid concentration at 0.1 M, pulp density at 20% w/v and the leaching time was for 120 minutes. Simulation results showed that the shrinking core model was inadequate to closely approach the experimental data. Meanwhile, the experimental data indicated that the leaching process was determined by the mobility of product molecules in the ash layer pores. In case of leaching resulting large product molecules, a mathematical model involving steps of reaction and product diffusion might be appropriate to develop.