D301R树脂对铬(Ⅵ)的吸附性能研究

Study on Adsorption of D301R Resin for Cr( VI)

在pH=2.63的HAc-NaAc体系中,D301R树脂对Cr(Ⅵ)有较好的吸附性。树脂的静态饱和吸附容量为206mg/g。用 5％NH4CI和10％NH3·H2O的混合液能定量洗脱,测得吸附速率常数k298=2.52×10^(-4)/s。吸附过程遵守Freundlich等温式。298K 时测得吸附热力学参数△H=3.33kJ/mol、△G=-6.96kJ/mol、△S=34.5J/(mol·K)。树脂功能基与Cr(Ⅵ)的配位比为1:1。

The adsorption properties of D301R resin for Cr (VI) have been studied at pH=2.63 in the medium of HAc-NaAc. The statically saturated adsorption capacity was 206 mg/g.resin. Cr (VI) adsorbed on D301R could be reductively eluated by 5% NH4C1-10% NH3· H2O. The adsorption rate constant was K298=2.52 × 10-4S-1 and the adsorption behavior of D301R for Cr (VI) obeyed the Freundlich isotherm. The themodynamic parameters of sorption: enthalpy change △H, free energy change △G and entropy change △S of adsorption (D301R) for Cr (VI) were 3.33kJ·mol-1, -6.96kJ1·mol-1, 34.51 ·mol-1.K-1,respectively. Coordination molar ratio of the functional group of D301R to Cr (VI) was 1:1.