金属网表面沉积纳米ZnO的制备及其油水分离性能研究

发布时间：2018-03-27 15:39

  本文选题：双亲性　切入点：油水分离　出处：《吉林大学》2017年硕士论文

【摘要】：在实际生产中,油中含不同程度的杂质,这些油不仅应用受到限制,还会导致环境问题。油中过高的水含量,使得油分层而无法继续使用,造成资源浪费。油水分离膜应运而生,成为一项新的研究领域。油水分离的主要目的是分离油中不相溶的水、甘油、酯类等,进行油的初级提纯。然而,油中极少量杂质的存在会降低油品质。例如,燃料油中一些芳烃和极性有机杂质的存在,会影响发动机燃烧性能;燃烧不充分,还会对环境造成不利影响。目前,以金属网为基底,表面沉积无机氧化物的滤膜已有报道。针对不同基底表面的沉积情况,对分离性能的影响以及基底孔径的选择没有提供明确的尺寸范围。众所周知,吸附是实现水净化作用有效的方法,吸附剂被广泛的应用在商业和日常生活中。然而,当前的吸附剂几乎不能应用于油中极性有机杂质的移除。根据以上分析,本论文由以下两部分组成:1.本论文通过NH_3·H_2O与Zn(NO_3)_2·6H_2O低温水热法调控不同条件制备纳米棒状ZnO。实验结果表明,反应时间对ZnO滤膜制备有较大的影响。由SEM、EDX等表征,Zn(NO_3)_2·6H_2O浓度为0.25 M,NH_3·H_2O体积为7 m L,反应温度95℃,反应时间5.5 h作为金属网表面沉积的最优条件。对不同基底制备的滤膜进行油水分离性能比较,我们发现,不锈钢网表面沉积的ZnO易脱落,分离效率低于表面沉积均匀的铜网。铜网作为沉积基底,孔尺寸的选择应小于500μm,否则滤膜易穿透,失去选择性。本征亲水的ZnO,通过Wenzel模型放大粗糙结构,制备的ZnO滤膜在空气中水的接触角接近0°,并且水中超疏油。基于其超亲水性,ZnO可以将水中少量浮油成功分离。2.纳米ZnO具有亲水-亲油的性质。空气中,油在ZnO滤膜表面的接触角接近0°。基于其超亲油性,ZnO能够进行油品粗纯化,将油中少量或微量水成功分离。因ZnO具有高的表面能和强极性,倾向于将低表面能的物质吸附在表面,以降低自身表面能。以分别溶解了极性染料Nile Red(NR)和Oil Red O(ORO)的十六烷溶液作为吸附对象,极性染料能够在ZnO表面吸附。当染料浓度为20ppm时,ZnO对十六烷中NR的吸附效率达到23%。由于ZnO与ORO之间可能存在氢键,ZnO对十六烷中ORO的吸附效率近70%。纳米ZnO对油中浓度低至1 ppm的染料都有很好的吸附,因此,高表面能的ZnO对油提纯具有一定的实用价值。
[Abstract]:In the actual production, the oil contains different degrees of impurity. These oils are not only limited in application, but also lead to environmental problems. Oil and water separation membrane emerged as a new research field. The main purpose of oil water separation is to separate insoluble water, glycerol, esters, etc. For example, the presence of some aromatic hydrocarbons and polar organic impurities in the fuel oil can affect the engine's combustion performance; the combustion is inadequate and also has a negative impact on the environment. Inorganic oxide film deposited on the surface of metal mesh has been reported. The influence on the separation performance and the choice of the substrate pore size are not provided for the different substrate surface deposition conditions. Adsorption is an effective method for water purification. Adsorbents are widely used in commercial and daily life. However, the current adsorbents can hardly be used to remove polar organic impurities in oil. This thesis consists of the following two parts: 1. In this thesis, nanorods were prepared by NH_3 H _ 2O and Zn(NO_3)_2 6H_2O under different conditions. The effect of reaction time on the preparation of ZnO filter membrane was studied by SEM edX. The concentration of 6H_2O was 0. 25 MN NH 3H 2O and the reaction temperature was 95 鈩，

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