自然水体采集的生物膜上铁、锰氧化物的萃取分离

采用选择性萃取分离技术对自然水体采集的生物膜上铁、锰氧化物进行萃取分离研究,考察该技术的适用性.参考人工培养生物膜的萃取方法,分别用NH2OH·HCl和Na2S2O4为萃取剂选择性萃取生物膜上的锰氧化物和铁、锰氧化物.实验中分别依次只改变萃取剂浓度、萃取液酸度或萃取时间,保持其它两个因素不变,分别考察这三个因素对萃取效果的影响,从中选出对铁、锰氧化物萃取率高而对有机质影响小的条件为最佳条件.用选定的最佳条件对不同时间和地点采集的生物膜进行萃取,发现对目的组分的萃取率可达70.8%～94.6%,而对非目的组分的影响很小(3.3%～11.0%),满足萃取分离的要求.这说明选择性萃取技术可以广泛应用于自然水体采集的生物膜上铁、锰氧化物的萃取分离.

Selective Extraction of Fe and Mn Oxides from Biofilms Collected in Natural Waters

Selective extraction technology is employed to study the separation of manganese oxides and iron oxides in biofilms sampled from natural waters and reviews its applicability. Resulting the extraction technology of artificial culturing biofilms, the hydroxylamine hydrochloride (NH_2OHHCl) was selected to extract manganese oxides, and sodium dithionite (Na_2S_2O_4) was used to separate manganese oxides and iron oxides. Optimum extraction conditions were determined by changing only one of the experimental conditions such as extraction concentrations, extraction liquid acidity and extraction time and by considering these three factors affecting the extraction effect. Under the selected optimum conditions, the target components in biofilms sampled at different times and sites are extracted with efficiencies between 70.8% and 94.6%, and the affects on non-target components are negligible(3.3%(11.0%).) It satisfies the requirement of the extraction and separation. It shows that selective extraction technology can be applied broadly to the extraction and separation of manganese oxides and iron oxides in biofilms sampled from natural waters.