Highly efficient adsorption of salicylic acid from aqueous solution by wollastonite-based imprinted adsorbent: A fixed-bed column study

Wollastonite based imprinted polymer (WMIP) for salicylic acid (SA) was prepared by using surface molecular imprinting technique on the surface of wollastonite. A continuous fixed-bed column study on WMIP was carried out at bed depths of 0.9-4.9cm, flow rates of 1-3mLmin^-1 with initial SA concentrations of 10-60mgL^-1 at temperatures of 298-318K. Breakthrough time of the fixed-bed increased with the increase in bed depth, but decreased with increasing initial concentration, flow rate and adsorption temperature. Adsorption of SA by WMIP fixed bed was an exothermic process. The experimental data was in good agreement with the Thomas model. WMIP had an excellent eluting performance and regenerate property with a desorption efficiency up to 96.02%. It was found that hydrogen bonding between SA and the surface of WMIP significantly affected the selective adsorption of SA from aqueous solution.