Rejection spectra of reverse osmosis membranes degraded by hydrolysis or chlorine attack
Rejection spectra of reverse osmosis membranes degraded by hydrolysis or chlorine attack
复制标题
因水解或氯攻击而降解的反渗透膜的截留谱
DOI：
10.1016/0011-9164(86)90001-9
复制
发表时间：
1986
期刊：
影响因子：
9.9
通讯作者：
Barbara Hall
中科院分区：
文献类型：
--
作者：
J. C. Watters;E. Klein;M. Fleischman;J. S. Roberts;Barbara Hall
对醋酸纤维素（CA）和聚酰胺（PA）膜进行24 h的加速降解，以确定固化温度和降解时间对跨膜通量以及盐（NaCl和CaCl2）、己糖和多糖膜排斥的影响。商用PA膜和我们实验室制作的一套CA膜在降解24 h后完全丧失了除盐能力，但对多糖仍保持100%的除盐能力，因此仍具有超滤功能。第二组CA膜在不同温度下固化。在45°C和55°C退火的CA膜比在75°C退火的CA膜降解得更快，这是基于它们更快地丧失了拒盐能力。在较低温度下退火的膜的这种快速降解，加上它们固有的较差的初始防盐性，使我们得出结论，用于反渗透应用的膜不应在约55°C以下固化。在此基础上，提出了一种简单的测试程序来区分故障反渗透装置的化学降解和严重失效。
Cellulose acetate (CA) and polyamide (PA) membranes were subjected to accelerated degradation for up to 24 h to determine the effects of curing temperature and degradation time on transmembrane flux and on the rejection by the membranes of salts (NaCl and CaCl2), hexose sugars and polysaccharides. Commercial PA membranes, and one set of CA membranes made in our laboratory lost all salt rejection ability after 24 h of degradation but maintained 100% rejection of polysaccharides, and thus still functioned as ultrafilters.A second set of CA membranes was cured at different temperatures. CA membranes annealed at 45°C and 55°C degraded faster than those annealed at 75°C, based on their faster loss of salt rejection ability. This rapid degradation of the membranes annealed at lower temperatures, coupled with their inherent poor initial salt rejection enforces the conclusion that membranes to be used in reverse osmosis application should not be cured below about 55°C.Based on the study, a simple test procedure is proposed to distinguish between chemical degradation and gross failure in malfunctioning reverse osmosis units.