The leaching kinetics of sphalerite with pyrite, in water saturated in
chlorine, has been investigated. The leaching rate of sphalerite and
pyrite increased with decreasing particle size, and with increasing st
irring rate and gas flow rate. Increase of reaction temperature caused
the leaching rate of sphalerite to increase, and that of pyrite to in
crease in the temperature range of 12-20 degrees C and to decrease in
the temperature range of 30-70 degrees C. The kinetics and mechanism o
f dissolution reaction for sphalerite and pyrite were found to be diff
usion controlled through the product layer. The activation energy for
sphalerite in the ore was calculated as 22.68 kj mol(-1). The activati
on energies for pyrite were calculated as 43.28 kj mol(-1) in the temp
erature range 12-20 degrees C and 8.37 kj mol(-1) in the temperature r
ange 30-60 degrees C. (C) 1998 Elsevier Science Ltd. All rights reserv
ed.