Nanoparticle filtration through microporous ECTFE membrane in an alcoholic solution
Nanoparticle filtration through microporous ECTFE membrane in an alcoholic solution
复制标题
DOI：
10.1016/j.seppur.2018.08.022
复制
发表时间：
2019-02
影响因子：
8.6
通讯作者：
Na Yao;B. Khusid;K. Sirkar;Derek J. Dehn
中科院分区：
文献类型：
--
作者：
Na Yao;B. Khusid;K. Sirkar;Derek J. Dehn
有机溶剂过滤是一个重要的工业过程。它被广泛应用于制药、化工、半导体、汽车装配等领域。在公开文献中报道的大多数颗粒过滤研究都涉及水悬浮介质。目前的工作已经开始了交叉流溶剂过滤行为的微孔乙烯三氟氯乙烯（ECTFE）膜使用12 nm的二氧化硅纳米粒子悬浮在含有25%乙醇的水溶液中的研究。在错流微滤（MF）的恒压操作模式中，在不同的时间间隔收集渗透物样品。不同实验的渗透物粒度分布（PSD）结果是相同的。尺寸小于100 nm的颗粒团聚体可以通过膜;观察到一些结垢。在6.9 × 103 Pag和1.4 × 104 Pag下，使用3.8 × 10− 3 kg/m3（3.8 ppm）的试验中，控制污垢的机制是孔隙堵塞。对于在27.6 × 103 Pag（4 psig）下使用3.8 × 10− 3 kg/m3（3.8 ppm）和在6.9 × 103、13.8 × 103和27.6 × 103 Pag（1、2和4 psig）下使用1.9 × 10− 3 kg/m3（1.9 ppm）进行的试验，其机理是膜阻力控制。在使用具有较低或较高颗粒浓度和较高跨膜压力的悬浮液的实验中，较少的颗粒嵌入膜孔中。这与MF后膜的孔流和扫描电子显微镜图像中的剪切速率值非常一致。在使用甲醇、乙醇和2-丙醇的溶剂过滤的死端操作模式中，在所有测试压力下渗透通量行为遵循J甲醇> J乙醇> J 2-丙醇。对于甲醇、乙醇和2-丙醇，根据过滤通量与跨膜施加压差的线性图的斜率确定的渗透率值（kg/m2-s-Pa）分别为3.9 × 10−4、2.3 × 10− 4和3.0 × 10− 5。对之前报道的溶剂吸附结果进行了进一步的探索。选定的溶剂的临界温度显示出更好的相关性，而不是溶解度参数与溶剂吸附。
Organic solvent filtration is an important industrial process. It is widely used in pharmaceutical manufacturing, chemical processing industry, semiconductor industry, auto assembly etc. Most of the particle filtration studies reported in open literature dealt with aqueous suspension medium. The current work has initiated a study of cross-flow solvent filtration behavior of microporous ethylene chlorotrifluoroethylene (ECTFE) membranes using 12 nm silica nanoparticles suspended in an aqueous solution containing 25% ethanol. In the constant pressure mode of operation of cross-flow microfiltration (MF), permeate samples were collected at different time intervals. The permeate particle size distribution (PSD) results for different experiments were identical. Particle agglomerates having less than 100 nm size can pass through the membrane; some fouling was observed. The governing fouling mechanisms for tests operated using 3.8 × 10−3kg/m3(3.8 ppm) at 6.9 × 103Pag and 1.4 × 104Pag were pore blocking. For tests conducted using 3.8 × 10−3kg/m3(3.8 ppm) at 27.6 × 103Pag (4 psig) and 1.9 × 10−3kg/m3(1.9 ppm) at 6.9 × 103, 13.8 × 103and 27.6 × 103Pag (1, 2 and 4 psig), the mechanism was membrane resistance control. Less particles got embedded in membrane pores in experiments operated using suspensions with lower or higher particle concentrations with a higher transmembrane pressure. This is in good agreement with the values of the shear rate in the pore flow and scanning electron microscope images of the membrane after MF. In the dead-end mode of operation of solvent filtration using methanol, ethanol and 2-propanol, the permeate flux behavior follows Jmethanol> Jethanol> J2-propanolat all testing pressures. The values of permeance (kg/m2-s-Pa) determined from the slope of the linear plot of filtration flux vs. the applied pressure difference across the membrane, were 3.9 × 10−4, 2.3 × 10−4and 3.0 × 10−5for methanol, ethanol and 2-propanol, respectively. Further exploration was made on solvent sorption results reported earlier. The critical temperature of selected solvents shows a better correlation with solvent sorption rather than the solubility parameter.