In Thailand, this tree is commonly planted in home gardens for ornamental purposes as well as for the leaves, which are rich in chemicals: the leaves contain several flavonoids, saponins and phytosterols [24], and a high tannin content of around 13% [25]. As far as the authors are aware, no investigation has yet reported on the biosorption of palladium (Pd(II)) and platinum (Pt(IV)) ions by the leaves of Indian almond (T. catappaL.). This material was chosen as a biosorbent for the present study because it is natural, easily available, and thus a low-cost biomass for adsorption of dissolved metal ions.