Use of X-ray absorption near edge structure (XANES) to identify physisorption and chemisorption of phosphate onto ferrihydrite-modified diatomite

► Chemisorption occurs together with physisorption during phosphorus adsorption onto ferrihydrite-modified diatomite. ► Chemisorption occurs in the bulk of ferrihydrite-modified diatomite (between 50 nm and 5 μm). ► Phosphorus physisorption occurs at the zone of ferrihydrite-modified diatomite shallower than 50 nm.