화학공학소재연구정보센터
Industrial & Engineering Chemistry Research, Vol.56, No.34, 9419-9428, 2017
Enhancement of Phosphate Adsorption on Zirconium, Hydroxide by Ammonium Modification
Surface modification of adsorbents plays a crucial role in its adsorption performance. Furthermore, the most important step in modification is to design the modification groups based on target pollutants. In this study, the phosphate adsorption performance of zirconium hydroxide was enhanced by different ammonium modification as a result of increasing utilization efficiency, of adsorption site. The maximum capacity is 1-55.04 mg/g from the zirconium hydroxide modified by dimethylamine. In comparison with undecorated zirconium hydroxide; the selectivity factors for Cl-, So(4)(2-), and NO3- are all raised by almost 2 times by dimethylamine modification. The mass transfer rate K-2 also increase 6 times using N-methylaniline and N-ethylmethylamine. Results from zeta-potential and FT-IR revealed that the enhanced adsorption capacity for phosphate were directly related to the inner-sphere complex and electrostatic interactions (quaternary ammonium groups and phosphate) and ligand exchange (the hydroxyl groups of zirconium hydroxide and phosphate). Moreover, the utilization ratios of hydroxyl groups on adsorbents were improved from 22.9% to 33.9% by dimethylamine modification, which is proved by XPS. At last, the modified zirconium hydroxide presents excellent performances of anti-interference in real wastewater. Overall, modified zirconium hydroxide is considered to have great potential for engineering application, and then the method of increased utilization of the adsorption site gives a new route for other adsorption systems.