The effect of pH on the removal of cadmium from aqueous solutions by dry leaves has been studied. Reed leaves showed a high capability of cadmium adsorption at almost any pH. The adsorption was particularly high at pH 1. Cypress, oak and pine leaves showed lower adsorption of cadmium ions at low pH values and this adsorption increased steadily at higher pH values. Reed and oak leaves have been found more efficient for removing cadmium from aqueous solutions than cypress and pine leaves in acidic, neutral or basic media. Reed was particularly efficient at very low pH which makes it suitable for removing cadmium from polluted water affected by acid rain. Almost all of the cadmium present in solutions having concentrations 10mg/L was removed by reed leaves within 24 hours.
Journal of Environmental Science and Health, Part A, Volume 34, Issue 4 July 1999 , pages 835 - 851