Determination of Cr (III) and Cr (VI) In Water by Selective Separation and Preconcentration on Hybrid Resin

Simple and rapid method has been developed for separation, preconcentration and determination of Cr(III) and Cr(VI) species in water by using selective hybrid R-Cu-(OH)2 resin (HCR). The effect of pH value on the adsorbed of Cr(VI) was investigated, Cr(VI) species can be retained on the HCR and eluted by 1.0 M of NaOH solution completely while Cr(III) can not adsorbed on HCR. Chromium species before and after separation process were measured with 1-5-diphenylcarbazide by using spectrophotometer. The results showed that the capacity of HCR on adsorbed of Cr(VI) was 3.43 mg g-1. The concentration of Cr(V) determined by different between total Cr and Cr(III). The recovery of the determination of Cr(III) and Cr(VI) were ( 93.0 % to 101% ) and (93.6 % to 105 % ) respectively , while the RSD were ( 0.99% -6.18% ) and ( 1.63%-7.3% ) for Cr(III) and Cr(VI) respectively.