Kozlowski Cezary A, Walkowiak Wladyslaw
Institute of Chemistry and Environment Protection, Pedagogical University of Czestochowa, Poland.
Water Res. 2002 Nov;36(19):4870-6. doi: 10.1016/s0043-1354(02)00216-6.
The transport through polymer inclusion membranes (PIMs) was found as the effective and selective method of chromium(VI) anions removal from chloride acidic aqueous solutions. The optimal PIMs content was as follows: 41 wt% of cellulose triacetate as the support, 23 wt% of tri-n-octylamine as the ionic carrier, and 36 wt% of o-nitrophenyl pentyl ether as the plasticizer. The results obtained show a linear decrease of permeability coefficient and initial flux values with source phase pH increase. Also linear decrease of initial flux in log-log scale with chromium(VI) concentration increase was observed. Value of slope of this relationship was found to be 0.96 which indicates a first order of chromium(VI) reaction with tri-n-octylamine at membrane/aqueous source interface. Transport of chromium(VI) through PIMs reduces the concentration of chromium(VI) in source aqueous phase from 1.0 to 0.0028 ppm, which is below permissible limit in drinking water in Poland. Competitive transport of chromium(VI), cadmium(II), zinc(II), and iron(III) from acidic aqueous solution across PIMs was found to be efficient for chromium(VI) (99%), and cadmium(II) (99%).
通过聚合物包容膜（PIMs）进行的传输被发现是从氯化酸性水溶液中去除六价铬阴离子的有效且选择性的方法。最佳的PIMs含量如下：作为支撑体的三醋酸纤维素为41 wt%，作为离子载体的三正辛胺为23 wt%，作为增塑剂的邻硝基苯基戊基醚为36 wt%。所得结果表明，随着源相pH值的增加，渗透系数和初始通量值呈线性下降。还观察到在对数-对数尺度上，随着六价铬浓度的增加，初始通量也呈线性下降。发现该关系的斜率值为0.96，这表明在膜/水源界面处，六价铬与三正辛胺的反应为一级反应。通过PIMs传输六价铬可将源水相中六价铬的浓度从1.0 ppm降低至0.0028 ppm，这低于波兰饮用水的允许限值。从酸性水溶液中通过PIMs竞争性传输六价铬、镉（II）、锌（II）和铁（III），结果表明对六价铬（99%）和镉（II）（99%）的传输效率很高。
