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A viscose rayon succinate (VRS) was synthesized using viscose rayon, succinic anhydride and DMSO. The VRS was well characterized by C 13 nuclear magnetic resonance, Fourier transform infrared analysis and properties of the VRS up taking trivalent metals from aqueous solution were investigated. Both esterification and carboxyl bonding of the VRS were assigned essentially at 1729 and 1693 cm À1 , respectively. And the essential band of bonding between metal and the material was determined at 1605-1639 cm À1 . The available adsorption capacity, degree of substitution and pKa of the VRS were 6.2 mequiv/g, 2.5 and 3.72, respectively. The adsorption of metal ions on the VRS follows the order of Cr 3þ > Al 3þ > Fe 3þwith maximum adsorptions capacities 1.48, 1.059 and 1.029 mmol/g. An equilibrium modeling, which is obtained from chemical potential and Boltzmann distribution, was demonstrated trivalent metal adsorption on the VRS in different pHs. Surface potential, É 0 , an effective ratio of surface equilibrium constants, K effect , the probability factor PðAÞ and a degree of protonation, 1 represent the physicochemical interactions between carboxyl group and metal ions.

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In this study, Fe-Mn-CO3 layered double hydroxide (LDHs) and Fe-Mn Double oxide (DOs) were synthesized by the co-recipitation methods for Se(IV) removal from aqueous solutions. The Se(IV) adsorption capacities and removal mechanism of Fe-Mn LDH and Fe-Mn DOs determined by batch and column experiments. The calculated Se(IV) adsorption capacities on Fe-Mn LDH and Fe-Mn DOs were 52.5 and 55.3 mg/g, respectively. Kinetic models applied to the adsorption of Se(IV) on the Fe-Mn LDH and Fe-Mn DOs calculated using pseudo-first, second-order, Elovich, and Intraparticle diffusion kinetic models and all kinetic parameters were calculated and discussed. Isotherm studies were also performed using Langmuir, Freundlich, Temkin, and Dubinin-Radushkevich equations in the temperature range of 283 - 323 K. Adsorption kinetics and isotherm experiments are well fitted pseudo-second order model and Freundlich isotherm, respectively. The production of this adsorbent is cost-effective for industrial applications.