Abstract

In this study, the dissolution kinetics of smithsonite as an alternative zinc source in trichloroacetic acid (TCA) solution was investigated. TCA can be derived from industrial waste acid in the pharmaceutical, biotechnology and chemical fields. Results showed that the dissolution kinetics conformed to the shrinking core model controlled by surface chemical reaction. The apparent activation energy of the reaction was calculated as 47.61 kJ/mol, indicating the obvious effect of temperature on the reaction rate. The reaction kinetic equation associated with the main influencing factors was eventually established as 1– (1–x)^–1/3 = [0.0002 (C)^0.384 (P)^0.969 exp(–5726T)] t. The high reaction speed of smithsonite in TCA solution shows that TCA has a dissolution effect on zinc oxide ores; thus, it can be employed as an advantageous organic leaching reagent environmentally friendly. In addition, the experimental parameters obtained provide basic data and reference for the leaching of other carbonate minerals of copper, zinc, lead and cobalt, among others, in an organic acid system.