细菌与二氧化硅胶体共存对界面乳化的影响

Effect of bacteria and colloidal silica coexist on formation of interfacial crud

研究细菌对二氧化硅胶体形成界面乳化物稳定性的影响。研究结果表明:不同细菌浓度下,二氧化硅胶体形成稳定界面乳化物的生成率基本相同,并随体系中细菌浓度的增加,萃取分相过程中乳化液滴聚结速度逐渐加快。细菌表面—OH和—NH键破坏了二氧化硅胶体结构,使溶液中出现了Si—O—H基团。细菌在二氧化硅胶体表面吸附后液滴间由静电排斥能转变为吸引能,使形成乳化液滴聚结能垒降低,从而加快了乳化液滴的聚结速度。

The effect of bacteria-colloidal silica absorption on the emulsion stability was studied. The results show that the coalescence rate of emulsion droplet is accelerated with the increase of bacteria density in the extraction process; and the product rate of interracial layer is equaled with different bacteria density. The silanol groups （Si--O--H） formed due to the interaction between the --OH and --NH bonding located on the surface of bacteria and the siloxane of colloidal silica. The coalescence barrier is reduced after bacteria adsorbed and the repulsive force between droplets transforms into the attractive force, which speeds up the droplet coalescence.