N-Vinylimidazole-Modified Post-Cross-Linked Resin with Pendent Vinyl Groups and Their Adsorption of Phenol from Aqueous Solution

Herein N-vinylimidazole (VIM) was employed as the polar monomer in the polymerization, and a series of VIM-modified post-cross-linked resins with vinyl groups were prepared by altering the initial cross-linking degree and mass percentage of toluene in the porogens. The results indicate that the initial cross-linking degree and the porogens have great influence on the porosity and adsorption performance. The resins with a higher initial cross-linking degree and a higher mass percentage of toluene in the porogens possess higher Brunauer-Emmett-Teller surface area and pore volume. Moreover, the Friedel-Crafts alkylation reaction induces the greater increased micropore area and micropore volume. HPDV-90%-50% with the initial cross-linking degree of 90% and using 50% (w/w) toluene and 50% (w/w) benzyl alcohol (TA) in the porogens has the largest equilibrium capacity to phenol. The equilibrium data are well characterized by the Freundlich model, and the isosteric heat of adsorption decreases dramatically with increasing the fractional loading. The adsorption can reach equilibrium within 80 min, and the intraparticle diffusion is the rate-limiting step. HPDV-90%-50% exhibits a dynamic capacity of 40.3 mg/mL wet resin at an initial concentration of 520 mg/L and a flow rate of 1.6 mL/min, and it can be completely regenerated with an excellent regeneration property.