Extraction kinetics of neodymium(III) from chloride medium in the presence of two complexing agents by D2EHPA using a constant interfacial area cell with laminar flow

Kinetic studies of the extraction of neodymium (Nd) from chloride medium in the presence of two complexing agents lactic acid (HLac) and citric acid (H(3)Cit) by D2EHPA (H(2)A(2)) in kerosene have been investigated using a constant interfacial area cell with laminar flow. The different parameters affecting the extraction rate such as stirring speed, temperature, specific interface area, hydrogen ion concentration, and H(2)A(2) concentration are separately studied and a rate equation is deduced. The experimental results demonstrate that, the rate of Nd(III) extraction is a diffusion controlled process at the interface rather than in the bulk phase, and it is first order with respect to H(2)A(2) and H+ concentrations. The rate-determining step is proposed on the basis of predictions derived from interfacial reaction models, and is in good agreement with the analysis of the experimental results. (C) 2016 Elsevier B.V. All rights reserved.