【Paper】

Effects of Basicity and Leachant pH on the Dissolution Rates of Molten Slag

Toshikatsu Maeda*, Tsunetaka Banba** and Tsuyoshi Mizuno*
* Japan Atomic Energy Research Institute
** Japan Nuclear Cycle Development Institute
† Correspondence should be addressed to Toshikatsu Maeda:
Japan Atomic Energy Research Institute
（2-4 Shirane, Tokai-mura, Naka-gun, Ibaraki, 319-1195 Japan）


Abstract
Static corrosion tests were performed for SiO2-CaO-Al2O3 slag specimens in aqueous solutions ranging from acidic to alkaline at 40℃ to observe the effects of the solution pH and slag basicity on the dissolution rates of the slag. The initial dissolution rates of the slag were investigated, and were obtained with little disturbance caused by the change of the leachant properties such as elemental concentrations or pH. The initial dissolution rates were evaluated by normalized elemental mass loss per day. It was found that the initial dissolution rates of the slag in acidic and alkaline leachants were higher than those in near neutral leachants. The basicity of the slag did not affect the initial dissolution rates of the slag in the alkaline solutions. The initial dissolution rates in acidic solutions increased in proportion to the basicity of the slag, which is probably a result of the dissolution properties of the network structure of the slag.


Key words: corrosion behavior, slag, initial dissolution rate, basicity, pH