Synthesis and application of Amberlite xad-4 functionalized with alizarin red-s for preconcentration and adsorption of rhodium (III)

A new chelating resin was prepared by coupling amberlite xad-4 with alizarin red-s through an azo spacer,characterized by infra-red spectroscopy and thermal analysis and studied for rh(iii) preconcentration usinginductively coupled plasma atomic emission spectroscopy (icp-aes) for rhodium monitoring in the environment.the optimum ph for sorption of the metal ion was 6.5. the sorption capacity was found 2.1 mg/g of resin for rh(iii). a recovery of 88% was obtained for the metal ion with 1.5 m hcl as eluting agent. kinetic adsorption datawere analyzed by adsorption and desorption times of rh(iii) on modified resin. scat chard analysis revealedthat the homogeneous binding sites were formed in the polymers. the linear regression equation wasq/c = –1.3169q + 27.222 (r2 = 0.9239), for rh were formed in the spe sorbent,kd and qmax for the affinity bindingsites were calculated to be 0.76 ?mol/ml and 20.67 ?mol/g, respectively. the equilibrium data and parameters ofrh(iii) adsorption on modified resin were analyzed by langmuir, freundlich, temkin and redlich–peterson models.the experimental adsorption isotherm was in good concordance with langmuir and freundlich models (r2 > 0.998)and based on the langmuir isotherm the maximum amount of adsorption (qmax) was 4.842 mg/g. the methodwas applied for rhodium ions determination in environmental samples. with high recovery ( > 80%).