Removal Kinetics of Phospho r u s in Plating Waste Solution by Using Yatugatake Volucanic Ash Soils

Abstract

Removal characteristics of phosphonate and phosphinate ions in electroless nickel plati ng waste solution with Yatugatake volcanic ash soil (Y-2) have been investigated from the standpoint of chemical kinetics. Phosphon ate and phosphinate ions in solution have been found to be removed by an anionexchange reaction between the ions in solution and OH^- ions of Y-2, accompanied with a neutralization reaction between H⁺ ions in solution and OH^- ions of Y-2. Rate determing steps of the removal reactions have been estimated to be a film diffusion control and the film mass transfer coefficients for the phosphonate and posphinate ions were 1.7 x 10^-4 cm/s and 5.0 x 10^-5 cm/s, respectively.