Kinetics of phosphate adsorption in a soil derived from volcanic ash

Abstract

The mode of phosphate interaction in an allophanic soil from Chile was studied. It is suggested that two distinct stages occur in the adsorption process. An initial adsorption reaction, whose activation energy at zero percent cobestma was 13 to 16 Kcal/mol, can be described by chemisorption techniques. The existence of a second stage, probably due to intraparticle diffusion, was also demonstrated.