Institute of Electronic Structure and Laser, Foundation for Research and Technology-Hellas, P.O. Box 1527, 711 10 Heraklion Crete, Greece.
Langmuir. 2012 Feb 7;28(5):2690-5. doi: 10.1021/la204991n. Epub 2012 Jan 23.
This study presents the synthesis of microporous polystyrene particles and the potential use of these materials in CO(2) capture for biogas purification. Highly cross-linked polystyrene particles are synthesized by the emulsion copolymerization of styrene (St) and divinylbenzene (DVB) in water. The cross-link density of the polymer is varied by altering the St/DVB molar ratio. The size and the morphology of the particles are characterized by scanning and transmission electron microscopy. Following supercritical point drying with carbon dioxide or lyophilization from benzene, the polystyrene nanoparticles exhibit a significant surface area and permanent microporosity. The dried particles comprising 35 mol % St and 65 mol % DVB possess the largest surface area, ∼205 m(2)/g measured by Brunauer-Emmett-Teller and ∼185 m(2)/g measured by the Dubinin-Radushkevich method, and a total pore volume of 1.10 cm(3)/g. Low pressure measurements suggest that the microporous polystyrene particles exhibit a good separation performance of CO(2) over CH(4), with separation factors in the range of ∼7-13 (268 K, CO(2)/CH(4) = 5/95 gas mixture), which renders them attractive candidates for use in gas separation processes.
本研究提出了微孔聚苯乙烯颗粒的合成方法，以及这些材料在沼气净化中用于 CO2 捕集的潜力。通过苯乙烯（St）和二乙烯基苯（DVB）在水中的乳液共聚合成了高度交联的聚苯乙烯颗粒。通过改变 St/DVB 摩尔比来改变聚合物的交联密度。通过扫描和透射电子显微镜对颗粒的尺寸和形态进行了表征。在超临界 CO2 干燥或苯中冷冻干燥后，聚苯乙烯纳米颗粒表现出显著的比表面积和永久微孔性。由 35 mol% St 和 65 mol% DVB 组成的干燥颗粒具有最大的比表面积，通过 Brunauer-Emmett-Teller 法测量为 205 m2/g，通过 Dubinin-Radushkevich 法测量为 185 m2/g，总孔体积为 1.10 cm3/g。低压测量表明，微孔聚苯乙烯颗粒对 CO2 与 CH4 的分离性能良好，分离因子在 7-13 范围内（268 K，CO2/CH4=5/95 混合气），这使得它们成为气体分离过程的有吸引力的候选材料。
