Adsorption Behavior and Mechanism of Macroporous Phosphonic Acid Resin for Lu~(3+)

The article is based on a research on the adsorption behavior and adsorption mechanism of macroporous phosphonic acid resin (PAR) for Lu 3+ and the influence of the medium's pH, adsorption temperature, adsorption time, etc on adsorbing Lu 3+ . The best value of medium's pH to the adsorption of PAR for Lu 3+ was found to be 4.92. The static adsorption maximum capacity of PAR for Lu 3+ is 220?mg·g -1 . The thermodynamic adsorption parameters are respectively ΔH=11.3?kJ·mol -1 , ΔS=46.3?J·mol -1 ·K -1 , ΔG=-2.50?kJ·mol -1 and the apparent activity energy is E_a=31.4?kJ·mol -1 . The adsorption behavior of PAR for Lu 3+ obeys the Freundlich isotherm. The apparent adsorption rate constant is k_ 298 =4.68 ×10 -5 ?s -1 . The coordinate ratio of the functional radical to Lu 3+ is approximately 4∶1. The best eluant is 1.0?mol·L -1 HCl. The adsorption mechanism of PAR for Lu 3+ was separately confirmed by chemical analysis and IR spectra.