All the reagents were of analytical grade and were prepared in deionized water. An aqueous
stock solution (1000mg/L) of Cr (VI) ion was prepared using potassium dichromate
(K2Cr2O7) salt. This was used as the source of Cr (VI) in the synthetic waste water. pH of the
solution was adjusted using 0.1N HCl or NaOH. Fresh dilute solution was used for each
experiment.