eversvd,+2 (14)

A simple and rapid method has been developed for the separation, preconcentration, and determination of Cr(III) and Cr(VI) species in water using a selective hybrid R-Cu-(OH)2 resin (HCR). The study investigated the effect of pH on the adsorption of Cr(VI), demonstrating that Cr(VI) can be retained on the HCR and eluted completely with a 1.0 M NaOH solution, while Cr(III) is not adsorbed. The chromium species before and after the separation process were measured using 1,5-diphenylcarbazide with a spectrophotometer. Results indicated that the HCR had a capacity for adsorbing Cr(VI) of 3.43 mg g-1. The concentration of Cr(VI) was determined by calculating the difference between total Cr and Cr(III). Recovery rates for the determination of Cr(III) and Cr(VI) ranged from 93.0% to 101% and 93.6% to 105%, respectively, with relative standard deviations (RSD) of 0.99%-6.18% and 1.63%-7.3% for Cr(III) and Cr(VI).