4-氟苯乙烯掺杂型季铵基疏水性CO2变湿吸附剂制备及性能

Preparation and performance of 4-fluorostyrene doped quaternary ammonium-based hydrophobic CO2 moisture swing adsorbents

摘要:

以D201阴离子交换树脂和醋酸纤维素（CA）为原料，采用相转化法制备成型的季铵化变湿吸附剂薄膜（QAM），再经掺杂含氟聚合物进行疏水性调控，制备含氟聚合物季铵化变湿吸附剂薄膜（QAM-氟聚合物）用作CO2吸附剂。采用SEM、FTIR、BET和静态水接触角测试仪对QAM和QAM-氟聚合物进行表征，通过CO2吸附和动力学实验，考察掺杂含氟聚合物类型对QAM-氟聚合物的CO2吸附性能的影响。基于疏水性及干燥性能测试和模型拟合，以及CO2吸附和动力学实验，探究4-氟苯乙烯（4FS）的掺加量对4FS掺杂季铵化变湿吸附剂薄膜性能的影响，并对最佳性能的吸附剂进行相对湿度CO2吸附响应测试和循环利用实验。结果表明，掺杂4FS可以显著改善QAM吸附剂的孔隙结构和疏水性，提高CO2吸附性能；当20%的CA质量用4FS掺杂替代时，制备的QAM-20%4FS性能最佳，在相对湿度22.5%~90%的条件下，CO2吸附容量保持在1.03~1.245 mmol/g，半吸附时间（t1/2）在4.15~7.3 min；在相对湿度为90.0%的条件下，其吸附容量和峰值吸附速率较QAM提高了37.86%和79.75%；QAM-20%4FS经过8次循环后，循环容量仍稳定在1.15~1.2 mmol/g，再生程度超过90%。

Abstract:

Using D201 anion exchange resin and cellulose acetate (CA) as raw materials, the quaternized hygroscopic adsorbent film (QAM) was prepared by phase inversion method, and then the hydrophobicity was regulated by doping fluorine-containing polymer to prepare a fluorine-containing polymer quaternized hygroscopic adsorbent film (QAM-fluoropolymer) as a CO2 adsorbent. The QAM and QAM-fluorinated polymers were characterized by SEM, FTIR, BET and static water contact angle tester. The effects of doped fluorine-containing polymer types on the CO2 adsorption performance of QAM-fluorinated polymers were investigated by CO2 adsorption and kinetic experiments. Based on the hydrophobicity and drying performance test and model fitting, as well as CO2 adsorption and kinetic experiments, the effect of 4-fluorostyrene (4FS) doping amount on the performance of 4FS doped quaternized moisture swing adsorbents film was investigated, and the best performance adsorbent was subjected to relative humidity CO2 adsorption response test and recycling experiment. The results show that doping 4FS can significantly improve the pore structure and hydrophobicity of QAM adsorbent, and improve the CO2 adsorption performance. When 20% of CA mass is replaced by 4FS doping, the prepared QAM-20%4FS has the best performance. Under the condition of relative humidity of 22.5%~90%, the CO2 adsorption capacity is maintained at 1.03~1.245 mmol/g, and the half adsorption time (t1/2) is 4.15~7.3 min. Under the condition of relative humidity of 90.0%, the adsorption capacity and peak adsorption rate increased by 37.86% and 79.75% compared with QAM. After 8 cycles, the cycle capacity of QAM-20%4FS is still stable at 1.15~1.2 mmol/g, and the regeneration degree is more than 90%.