Dissolution rate of magnesium hydrate for wet flue gas desulfurization was measured by a pH-stat method. It was found that the dissolution rate of magnesium hydrate was controlled by mass transfer. As can be seen from the experimental results, the dissolution rate of magnesium hydrate increases with increasing reaction temperature and stirring speed. Lower pH value is favorable to the dissolution process of magnesium hydrate. And sulfate can promote the dissolution of magnesium due to the formation of bisulfate. (C) 2010 Elsevier Ltd. All rights reserved.