摘要
为了获得具有高效分离CO_(2)性能的膜材料,选用1-乙烯基咪唑(VIM)为油相,1-丁基-3-甲基咪唑三氟甲磺酸盐(BmimOTF)为表面活性构筑反胶束微乳液合成ZIF-8纳米粒子,再通过微乳液聚合制备ZIF-8/PVIM乳胶液,将其与聚酰亚胺(PI)共混制备混合基质膜.同时,结合气体吸附和渗透实验系统研究了微乳液组成对混合基质膜CO_(2)分离性能的影响规律.结果表明:由于微乳液中纳米反胶束的保护,合成的ZIF-8粒子平均粒径小于30 nm;随微乳液中表面活性剂及水相中配体浓度的增加,合成的ZIF-8粒子数增多且粒径也有所增大.所制备的混合基质膜中分子传质通道增多,膜的CO_(2)渗透性显著提高,CO_(2)分离选择性呈先增大后减小的趋势,但变化的幅度较小;微乳液中油相增多,合成的ZIF-8粒子粒径有所减小,所制备的混合基质膜中分子扩散传质通道减少,膜的CO_(2)渗透性减小,CO_(2)分离选择性也有所下降.在优化的微乳液组成及乳胶液掺杂量下,所制备的ZIF-8/PVIM-PI混合基质膜的CO_(2)渗透系数P_(CO_(2))可达1862.6×10^(-16) mol·m^(-1)·s^(-1)·Pa^(-1),CO_(2)分离选择性α_(P(CO_(2)/N_(2)))和α_(P(CO_(2)/CH_(4)))均大于40.
To obtain a membrane with efficient CO_(2) separation performance,1-vinylimidazole(VIM)and 1-butyl-3-methylimidazolium trifluoromethanesulfonate(BmimOTF)were used as the oil phase and the surfactant to construct reverse microemulsion to synthesize ZIF-8 nanoparticles,respectively.Following that,ZIF-8/PVIM latex via microemulsion polymerization was blended with polyimide(PI)to fabricate mixed matrix membranes(MMMs).Combining the gas adsorption and gas permeation experiments,the influence of the microemulsion composition and doping amount of ZIF-8/PVIM latex on CO_(2) permeability and gas selectivity for CO_(2) of MMMs were investigated.Results showed that the average particle size of the prepared ZIF-8 was less than 30 nm due to the protection of the nanoreactor in the reverse microemulsion.With the increase of ligand and surfactant in the aqueous phase of the reverse microemulsion,more ZIF-8 with larger sizes were generated.the resulting MMMs had more molecular diffusion mass transfer channels,and CO_(2) gas permeability was also greatly increased.The selectivity of the membrane for CO_(2) separation showed a slight trend of first increasing and then decreasing.The oil phase in the microemulsion increased,the particle size of the ZIF-8 decreased,the molecular diffusion mass transfer channels in the resulting MMMs decreased.So,the CO_(2) gas permeability of MMMs decreased,and the selectivity of the membrane for CO_(2) separation also decreased.Under the optimized microemulsion composition and dopant amount of latex,the optimal CO_(2) permeability coefficient of the ZIF-8/PVIM-PI MMMs could reach 1862.6×10^(-16) mol·m·m^(-2)·s^(-1)·Pa^(-1).These MMMs also had the highestα_(P(CO_(2)/N_(2)))andα_(P(CO_(2)/CH_(4))),which were above 40.
作者
杜诗雯
童诚
罗涛
吴礼光
王挺
DU Shiwen;TONG Cheng;LUO Tao;WU Liguang;WANG Ting(School of Environmental Science and Engineering,Zhejiang Gongshang University,Hangzhou 310012;Zhejiang Environmental Technology Co.Ltd.,Hangzhou 310018)
出处
《环境科学学报》
CAS
CSCD
北大核心
2023年第11期270-281,共12页
Acta Scientiae Circumstantiae
基金
国家自然科学基金(No.22078291,21776250)
浙江工商大学“数字+”学科建设管理项目(No.SZJ2022B014)。
