2011 年 45 巻 3 号 p. 147-157
Water is most important transport media for elements under earth surface condition. Most of the elements are dissolved from rocks by water, while those are removed from water by rocks. The mobility of the elements is governed by these processes. The transport of the elements via water under the surface condition has been studied for understanding of weathering of rocks and formation of ore deposits. Recently, pollutions of water and soils by toxic elements have become the environmental concern. Therefore, this topic also has become an important subject to understand the behavior of toxic elements at earth surfaces. I have studied (1) the chemical reactions that govern the distributions of elements between water and rocks and (2) the quantitative prediction of element distributions based on the chemical reactions under the surface condition. In the latter, I am focusing on adsorption processes of minerals' surface, that are not still well understood so far. A quantitative way to consider the adsorption processes is surface compelxation modeling. In this paper, I briefly review the history and current status of surface complexation modeling.
