XDLVO理论解析有机物在膜蒸馏过程中的膜污染行为机制  

Mechanism of membrane fouling in membrane distillation process by organic compounds:XDLVO theory

作　　者：王可 樊华 侯得印[2] 王军[2] WANG Ke;FAN Hua;HOU De yin;WANG Jun(Key Laboratory of Poyang Lake Environment and Resource Utilization,Ministry of Education,School of Environmental and Chemical Engineering,Nanchang 330031,China;National Engineering Research Center o£Industrial Wastewater Detoxication and Resource Recovery,Research Center for Eco-Environmental Sciences9 Chinese Academy of Sciences?Beijing 1000859 China)

机构地区：[1]南昌大学资源环境与化工学院鄱阳湖环境与资源利用教育部重点实验室,南昌330031 [2]中国科学院生态环境研究中心工业废水无害化与资源化国家工程研究中心,北京100085

出　　处：《膜科学与技术》2022年第2期25-33,共9页Membrane Science and Technology

基　　金：国家自然科学基金项目(51878659);军队后勤科研重大项目(AWS18J004)。

摘　　要：采用XDLVO(Extended Derjagu-Landau-Verwey-Overbeek)理论对商用微孔疏水膜(PVDF膜)与自制超疏水膜(SH-PVDF膜)在膜蒸馏(MD)处理高盐有机(腐殖酸(HA)、海藻酸钠(SA))废水过程中的膜污染行为机制进行定量解析,评价不同界面相互作用能(范德华(LW)作用能、静电(EL)作用能、路易斯酸碱(AB)作用能)对膜污染的影响程度,并采用气隙式膜蒸馏(AGMD)进行对比验证.结果表明:LW与EL作用能为正值,AB作用能为负值且在几种作用能中起主导作用、导致总界面相互作用能为负值,污染物与膜界面间表现为吸引作用,说明所考察的几种有机物都会对2种膜材料产生一定程度的污染;膜的受污染程度与膜和污染物的极性性质有关;对于同一种污染物,PVDF膜更容易受到污染;对于同一种膜而言,HA比SA更容易造成膜污染;另外,Ca^(2+)的加入会加重膜污染.AGMD运行实验与计算结果一致,表明XDLVO理论对于有机物在膜蒸馏过程中的膜污染行为解析具有指导意义.The XDLVO(Extended Derjagu-Landau-Verwey-Overbeek)theory was used to quantitatively analyse the membrane fouling behavior mechanism of different membranes including a commercial microporous hydrophobic membrane(PVDF membrane)and a super hydrophobic membrane(SH-PVDF membrane).The theory was applied to the membrane distillation(MD)process of treating high-salt wastewater containing organic pollutions accounting for humic acid(HA)and sodium alginate(SA).Then the theory was utilized to evaluate the effect of different interfacial interactions which consist of Lifshitz van der Waals(LW),electrostatic(EL)and acid-base(AB)on the membranes fouling,and the air gap membrane distillation(AGMD)experiments were conducted to verify the calculation results.The results indicated that LW and EL were positive,while AB was negative and played a dominant role in the three interfacial energies.Thus the total interfacial interaction energy was negative and expressed as an attraction effect,indicating that the organic pollutions would pollute the membranes to a certain extent.The degree of membrane fouling was related to the polarity of membrane and pollutants.The SH-PVDF membrane was more difficult to be polluted by both of the two pollutions,and for the same membrane,HA was more likely to cause membrane fouling than SA.Furthermore,the membrane fouling would be aggravated with the addition of Ca^(2+).The AGMD experiment results were consistent with the calculation which indicated the theory is instructive to the analysis of membrane fouling behavior of organic compounds in MD process.

关 键 词：XDLVO理论 膜污染 疏水膜 有机物 气隙式膜蒸馏 

分 类 号：TQ028.8[化学工程]