Static adsorption of succinic acid with comb weakly basic resin (MKF-D30X)

The aim of this work is to study the adsorption of succinic acid on MKF-D30X resin which is a novel comb-shaped weak base anion resin with diethyl-amine-functional groups, high adsorption capacity and high freedom degree. MKF-D30X resin was synthesized by using the Glycidyl methacrylate (GMA) as monomer and the chloroacetyl poly(styrene-divinylbenzene) (PS-acyl-Cl) as initiator, via atom transfer radical polymerization (ATRP) to form comb-like graft polymer and then to be aminated. The influences of the various experimental parameters, such as pH value, concentration of succinic acid, adsorption time and temperature, were investigated by static adsorption experiments. The experimental results show that the amount of the succinic acid adsorption increases with the increase of the succinic acid concentration and the adsorption time, and the decrease of the pH value and temperature. The obtained results are in agreement with the Langmuir model. Adsorption of succinic acid reaches equilibrium in 130 min, and the adsorption kinetics of succinic acid from aqueous solution could be described by the Pseudo-second order equation. It was demonstrated that the intrapartical diffusion is the rate controlling step. When the concentration of succinic acid is 20 g·L^-1, under the optimum conditions obtained, the adsorption capacity of succinic acid is about 421 mg·g^-1 of adsorbent and which is 40% higher than that of commercial resin D301-1. Desorption experiment was performed by using elution agent of 1.0 mol·L^-1 HCl, the desorption efficiency is 98% and after five times reusing, the adsorption performace of the resin is not reduced. The high adsorption and desorption capacity of the MKF-D30X are attributed to the advantages of it having comb-like flexible chain structure and a large degree of freedom.