膜污染层微生物与聚丙烯微滤膜间的界面作用及其吸附特征

The adsorption characteristics of microorganisms isolated from biofouling layer of MBR and the interaction between the microorganisms and polypropylene microfiltration membrane

采用热力学方法及界面吸附理论,对2株膜污染层微生物(Aeromonas veronii M4、Aeromonas caviae N25)与聚丙烯(PP)微滤膜间的界面作用及吸附特征进行研究.结果表明,Aeromonas veronii M4与PP膜表面均表现出明显的疏水性特征,而Aeromonas caviae N25则呈现亲水性特征,并且A.veronii M4的运动性能也要高于A.caviae N25;另外,2株细菌及PP膜的表面均带有负电荷,表现出明显的电子供体特征,而Lewis酸碱分量U_(mlb)^(AB)则在2株细菌与PP膜的界面作用能中占据着主导地位;依据XDLVO理论,A.caviae N25及A.veronii M4与PP膜之间的总界面作用能均为负值,表明二者在膜上的吸附是一个主动吸附过程,而A.veronii M4-PP膜之间的界面作用能负值最大,说明A.veronii M4具有较高的吸附能力;静态吸附结果则表明,A.veronii M4在PP膜上的吸附量要明显高于A.caviae N25,而2株菌在膜上的吸附行为可由准二级动力学模型进行描述.

In this study,the adsorption characteristics of two bacteria strains isolated from biofouling layer of MBR and interaction between bacteria and polypropylene（ PP） microfiltration membrane were studied by using the thermodynamic method and the interfacial adsorption theory. The results show that the surfaces of A.veronii M4 strain and PP membrane exhibited obviously hydrophobic properties,however,A.caviae N25 had a hydrophilic surface. The motility of A.veronii M4 strain was higher than that of A. caviae N25. In addition,both of the two bacteria and PP membrane surfaces were negatively charged and displayed the typical electron donor characteristics. The Lewis acid-base interactions of both bacterium-membrane systems occupied a dominant position among the various interfacial interaction energy components. According to the XDLVO theory,the total interfacial interaction energy of two systems was negative,which indicates the adsorption potentials of both strains to the PP membrane. Compared with the A. caviae N25-PP membrane system,the A. veronii M4-PP membrane combination had the relative lower（ negatively greater） interfacial interaction energy,which suggeste that A.veronii M4 might be favored to the PP membrane. Moreover,the results of the static adsorption results demonstrate that the quantity of A. veronii M4 adsorbed on PP membrane was significantly higher than that of A. caviae N25. The adsorption process of both bacterium-membrane systems could be described by the pseudo-second-order kinetics equation.