Dissolution kinetics of natural magnesite in acetic acid solutions

Dissolution of magnesite in acetic acid solutions was investigated. The influence of various parameters such as reaction temperature, particle size and acid concentration was studied in order to elucidate the kinetics of magnesium carbonate. The leaching rate increased with decreasing particle size and with increasing temperature. Initially, the dissolution in terms of acid concentration increased until a definite concentration and then fell with increasing concentration. A kinetic model was researched to describe the dissolution and to analyse the kinetic data, basically. Dissolution curves were evaluated in order to test shrinking core models for fluid-solid systems. Consequently, it was determined that the dissolution of natural magnesite was controlled by chemical reaction, i.e., 1-(1-x)1/3=kt. The apparent activation energy of leaching process was found as 78.40 kJ mol(-1). (C) 2004 Elsevier B.V. All rights reserved.