Abstract: In the present study, an adsorbent was prepared from tamarind seeds and batch studies were conducted for
Cr(VI) removal from aqueous solutions. Tamarind seeds were activated by heat treatment and with concentrated sulfuric
acid (98% w/w). The parameters investigated include initial pH, contact time, initial Cr(VI) concentration, and adsorbent
dosage. The adsorption of Cr(VI) was found to be maximum at low values of initial pH in the range of 1–3. The adsorption
process of Cr(VI) was tested with Langmuir and Freundlich isotherm models. Application of the Langmuir isotherm
to the systems yielded maximum adsorption capacity of 29.08 mg g–1. The adsorption process followed second order kinetics
and the corresponding rate constant was found to be 0.0026 g mg–1 min–1.