摘要
采用超滤法和层析法分离纯化聚合氯化铝 (PAC)中的Al1 3 形态 ,并采用Al Ferron逐时络合比色法、2 7Al NMR、TEM和粒度测定仪对分离纯化所得的Al1 3 形态进行了分析和表征 .研究结果表明 ,超滤法分离纯化的效果受超滤膜的孔径及PAC浓度的影响 ,选择合适孔径的膜和PAC溶液浓度即可以获得高纯度的Al1 3 ,在层析法中则随着洗脱时间延长按分子的大小依次洗脱下来 ,因此截取中间组分即可得到Al1 3 ;Al Ferron逐时络合比色法和2 7Al NMR的分析结果表明 ,采用上述 2种方法分离提纯得到的样品中Al1 3 的含量分别可达到 90 %以上和 1 0 0 % .TEM和粒度测定结果表明 ,在B =2 5的PAC溶液中 ,Al1 3 极少以Al1 2 AlO4(OH) 2 4(H2 O) 7+ 1 2 的单体形态存在 ,而是呈两维结构的线性和枝状的聚集体 ,Al1 2 AlO4(OH) 2 4(H2 O) 7+ 1 2 的聚集体尺寸通常在几十至几百nm .
The polynuclear Keggin species, Al 12 AlO 4(OH) 24 (H 2O) 7+ 12 (Al 13 ), was firstly separated and purified from polyaluminum chloride (PAC) by the ultra filtration and column chromatography method. The Al 13 yield was characterized by Al Ferron timed complexation spectrophotometry, 27 Al NMR,TEM and ZATESIZER 3000HSA.The results showed that the purified sample by the ultra filtration method influenced by membrane pore radius and the concentration of PAC solution. High purity Al 13 would be obtained by choosing appropriate membrane and concentration of PAC. When using the column chromatography method, the bigger molecules were eluated first, then the smaller ones. Al 13 would be obtained by taking out the middle educt. From Al Ferron timed complexation spectrophotometry, it was found that the obtained sample contained more than 90% and 100% of Al 13 by using the two methods mentioned above respectively. The TEM and ZATESIZER 3000HSA results showed that Al 13 was mainly aggregated as line type and branch type in B=2.5 solution, and the size was about several decade and several hundred nm.
出处
《环境科学》
EI
CAS
CSCD
北大核心
2004年第5期75-79,共5页
Environmental Science
基金
国家高技术研究发展计划 ( 863计划 )项目( 2 0 0 2AA60 12 90 5 )
高等学校博士点专项科研基金资助项目 ( 2 0 0 2 0 42 2 0 0 1)
山东省自然科学基金项目(Y2 0 0 2B0 3 ) .
关键词
AL13形态
分离纯化
聚合氯化铝(PAC)
形态表征
Al 13 species
separation and purification
polyaluminum chloride(PAC)
characterization of morphology
