Chemical Interactions of Dissolved Silica With Iron (II) and (III)

In defining the role of dissolved silica in water quality transformations, it is essential first to obtain sufficient information regarding the chemical nature of the various species of silica, which may exist under different conditions in dilute aqueous solution. Secondly, considerations must be given to the chemical interaction of these species with other major components of natural waters, and with the various materials added in the course of water treatment. This article describes some of the results of an investigation of several of the reactions of dissolved silica in dilute solution. In recognition of the role of chemical interactions in coagulation processes, the effects of silicic acid on iron hydrolysis may eventually help to explain the mechanisms by which polymeric‐activated silica functions as a coagulant aid.