仿鱼鳞PDA纳米片复合滤膜的制备及油水分离性能

以聚多巴胺(PDA)为原料、Mg(OH)₂为模板剂，采用液相沉积法原位包覆Mg(OH)₂纳米片制备了PDA纳米片，再以疏水棉布为基底，PDA纳米片为覆盖层制备了PDA纳米片复合滤膜(简称复合滤膜)。通过SEM、TEM、BET、FTIR、XPS、XRD和接触角测量仪对复合滤膜进行了结构表征，同时测定了复合滤膜对油水混合物和乳化油的分离性能、循环使用性能和抗污染性能。结果表明，PDA纳米片的引入显著地增加了复合滤膜的表面粗糙度，在自重作用下复合滤膜对油水混合物和乳化油(均以环己烷为油相)的渗透通量分别为2866.24和1015.13 L/(m²·h)，分离效率达99.5%，且复合滤膜在重复使用10次后，其对乳化油的渗透通量为798.11 L/(m²·h)，分离效率达98.1%。此外，PDA纳米片还具有普适性，能覆盖在不同基底上进行乳化油分离，具有良好的应用前景。

Preparation and oil-water separation performance of fish scale-like PDA nanosheets composite filter membrane

PDA nanosheets were prepared by in-situ coating magnesium hydroxide nanosheets with hydrophobic cotton cloth as the substrate, polydopamine (PDA) as the raw material and magnesium hydroxide as the template, and then PDA nanosheets composite filter membrane (referred to as composite filter membrane) was prepared with hydrophobic cotton cloth as the substrate. The structure of the composite filter membrane was characterized by SEM, TEM, BET, FTIR, XPS, XRD and contact angle tester. The separation performance, recycling performance and anti-pollution performance of the composite filter membrane for oil-water mixture and emulsified oil were measured. The results showed that the introduction of PDA nanosheets significantly increased the surface roughness of the composite membrane. Under the condition of self-weight, the permeation fluxes of the composite membrane for oil-water mixture and emulsified oil were 2866.24 and 1015.13 L/(m2?h), respectively, and the separation efficiency was 99.1%. The permeation flux of the composite membrane for emulsified oil was 789.11 L/(m2?h) and the separation efficiency was 98.1% after repeated use for 10 times. In addition, PDA nanosheets also have universality and can cover different substrates for emulsified oil separation, which has good application prospects.