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氧化铁硫杆菌在摇动烧瓶细菌培养器中培育,使用粉状硫作能源,培养细菌后检测介质的pH值。低水平(10ppm)的可溶性硝酸银(AgNO_3)被引入某些细菌培养物,它被细菌所吸附。银吸附导致了在发育期中的延时,但不降低其后的发育速率。吸附也使细菌颜色从明亮的硫黄色变为深灰色。使用颗粒显微电泳技术对银负载的细菌和对照细菌培养物进行了ζ电势测定。发现对照细菌培养物的ζ电势与其他研究的结果一致。在pH2.4时具有IEP。银负载细菌的ζ电势则大为不同,在pH低于2.0时显示IEP,pH7.0时具有最大ζ电势-32mV。在较高pH条件下,ζ电势增加。也测定了纯硫化银的ζ电势,发现其IEP和对照细菌培养物相似。在IEP和pH5之间,银负载细菌的ζ电势接近对照细菌培养物的纯矿物ζ电势之和。假设提高的ζ电势是由于硫化银沉淀的附加表面电势所造成的。结果引发了银吸附细菌选择性回收的可能性以及新的银回收系统。
Thiobacillus ferrooxidans was cultivated in a shaking flask in a bacterial incubator using pulverized sulfur as an energy source to detect the pH of the medium after the bacteria were cultured. Low levels (10 ppm) of soluble silver nitrate (AgNO 3) are introduced into certain bacterial cultures and are adsorbed by bacteria. Silver adsorption leads to a delay in development but does not reduce subsequent growth rates. Adsorption also changes the color of the bacteria from bright yellow to dark gray. Zeta potential measurements were performed on silver loaded bacteria and control bacterial cultures using particle microscopic electrophoresis techniques. The zeta potential of control bacterial cultures was found to be consistent with the results of other studies. IEP at pH 2.4. The zeta potential of silver-loaded bacteria is then quite different, showing IEP at pH below 2.0 and -32 mV at pH 7.0. At higher pH, the zeta potential increases. The zeta potential of pure silver sulfide was also determined and found to be similar to that of control bacterial cultures. Between IEP and pH5, the zeta potential of the silver-loaded bacteria was close to the sum of the pure mineral zeta potential of control bacterial cultures. The increased zeta potential is assumed to be due to the additional surface potential precipitated by the silver sulphide. The result led to the possibility of selective recovery of silver-adsorbed bacteria as well as the new silver recovery system.