【摘要】 以大肠杆菌和金黄色葡萄球菌为模型微生物,研究了TiO2/蒙脱石复合光催化剂的抗菌性能。分析了光照射方式、细菌接种世代对光催化抗菌效果的影响,并从悬菌液初始浓度、催化剂用量和缓冲液三方面考察了反应的动力学行为。实验结果表明,75 min内,TiO2/蒙脱石对两种细菌的灭菌率均达到99%左右;间歇光照射与连续光照射时的抗菌效果较为接近;细菌接种世代越多,其对光催化作用的敏感性越强。当菌液浓度为103~107cfu/mL时,TiO2/蒙脱石光催化抗菌反应符合表观拟1级反应动力学模型;催化剂用量与反应速率常数呈二次抛物线关系;使用不同的缓冲液,抗菌反应速率由大到小的顺序为:PBS(磷酸盐缓冲液)<生理盐水<无菌蒸馏水。更多还原

【Abstract】 The antibacterial capability of TiO2/Montmorillonite(TiO2/MMT) nano-composite photocatalyst was investigated by employing Escherichia coli and Staphylococcus aureus as the target organisms.The effect of illumination mode and generations of the bacterial on bactericidal efficency of TiO2/MMT was analyzed.And the antibacterial kinetic behavior was revealed from the aspects of initial bacterial concentration,photocatalyst dosages as well as the type of buffer solution.Experimental results showed that the disinfection rate for the target orgainisms reached about 99% in 75 min by TiO2/MMT,and the bactericidal efficiency under intermittent and continuous illumination mode was quite close to each other.The higher the generation was,the more sensitive would be the bacteria response to the photocatalysis.The photocatalytic disinfection of TiO2/MMT followed the pseudo first-order reaction model when the bacterial concentration was 103-107 cfu/mL.The relation between the photocatalyst dosage and the antibacterial rate constant was assumed to be a parabola equation.The antibacteria rate sequence for different buffer solutions was phosphate buffer saline<physiological saline<distilled water.更多还原