摘要
We synthesized one quaternary ammonium polymeric ionic liquids(PILs)P[VBTHEA]Cl and three imidazolium PILs of P[VEIm]Br, P[VEIm]BF, P[VEIm]PFby free-radical polymerization in solution. These PILs were characterized by FT-IR,H-NMR,C-NMR, TGA, XRD and SEM. Their COadsorption capacities were measured under different pressures and temperatures by constant-volume technique. It was observed that quaternary ammonium PILs of P[VBTHEA]Cl have higher adsorption capacity for COthan those imidazolium PILs, following P[VBTHEA]Cl > P[VEIm]PF> P[VEIm]BF> P[VEIm]Br, which may be ascribed to higher positive charge density on ammonium cation than that on imidazolium cation and thus stronger interaction with CO, consistent with the results from dual-mode adsorption model that ammonium PILs have much higher CObulk absorption than imidazolium PILs. COadsorption capacity of P[VBTHEA]Cl is 9.02 mg/g under 295 K and 1 bar, which is comparable to that of some other PILs, and is much higher than that of the corresponding ILs monomer. These PILs have good adsorption selectivity for COover Nand regeneration efficiency.
We synthesized one quaternary ammonium polymeric ionic liquids(PILs)P[VBTHEA]Cl and three imidazolium PILs of P[VEIm]Br, P[VEIm]BF_4, P[VEIm]PF_6 by free-radical polymerization in solution. These PILs were characterized by FT-IR,~1 H-NMR,^(13)C-NMR, TGA, XRD and SEM. Their CO_2 adsorption capacities were measured under different pressures and temperatures by constant-volume technique. It was observed that quaternary ammonium PILs of P[VBTHEA]Cl have higher adsorption capacity for CO_2 than those imidazolium PILs, following P[VBTHEA]Cl > P[VEIm]PF_6> P[VEIm]BF_4> P[VEIm]Br, which may be ascribed to higher positive charge density on ammonium cation than that on imidazolium cation and thus stronger interaction with CO_2, consistent with the results from dual-mode adsorption model that ammonium PILs have much higher CO_2 bulk absorption than imidazolium PILs. CO_2 adsorption capacity of P[VBTHEA]Cl is 9.02 mg/g under 295 K and 1 bar, which is comparable to that of some other PILs, and is much higher than that of the corresponding ILs monomer. These PILs have good adsorption selectivity for CO_2 over N_2 and regeneration efficiency.
基金
financially supported by State Key Laboratory of Organic-Inorganic Composites(oic-201601012)
the International Scientific Partnership Program ISPP at King Saud University for funding this research work through ISPP#0080