Abstract:In order to solve the issue of poor recyclability of oil/water separated filter membrane, tannic acid-copper (TA-CuⅡ) was adhered by supramolecular binder of tannic acid-polyvinyl alcohol (TA-PVA) to form tannic acid-polyvinyl alcohol-copper (TA-PVA-CuⅡ) coating modified polyvinylidene fluoride (PVDF) filter membrane, and the superhydrophilic/underwater superoleophobic TA-PVA-CuⅡ@PVDF membrane with stable micro-nano coating was prepared. The results showed that under the function of hydrophilic micro-nano coating of TA-PVA-CuⅡ, the water contact angle and underwater oil contact angle of TA-PVA-CuⅡ@PVDF membrane respectively was 0° and 151.0°. In addition, the membrane flux and separation efficiency of TA-PVA-CuⅡ@PVDF membrane about emulsified oil could reach 1169.30 L/(m2·h) and 99.99%, respectively, which exhibited excellent oil/water separation performance. Moreover, the effect of CuⅡ modification time on the recyclability and coating durability of TA-PVA-CuⅡ@PVDF membrane was compared and analyzed. It was found that the TA-PVA-CuⅡ@PVDF membrane modified by CuⅡ for 20 min had the best recyclability and coating durability with 15 cycles of separation times and the flux change rate of which was 6.6%.