Preparation of shrimp shell powder-PVDF filtration membrane and its application in oil-water separation

Abstract

Abstract In recent years, the problem of ship-related oily wastewater discharge has escalated due to the growing ship trade. Consequently, the hydrophobic modification of polyvinylidene fluoride (PVDF) membranes has gained significant traction within the oil-water separation technology domain as a potential solution. This study presents a new membrane composed of shrimp shell powder, tannic acid (TA), polyvinyl alcohol (PVA), and PVDF with excellent hydrophilicity and micro-nano porosity. The preparation method is simple, non-toxic, and environmentally friendly. Shrimp shell powder is beneficial to modify the hydrophobic PVDF membrane. The strongly adhesive TA-PVA complex helps to improve the durability of shrimp shell powder in TA-PVA-PVDF membranes. Shrimp shell powder was evenly coated on the PVDF (polyvinylidene difluoride) membrane by vacuum filtration to prepare the TA-PVA-PVDF filter membrane with superhydrophilic-underwater hydrophobicity. The initial efficiency of the emulsified oil-water mixture in the separation experiments reached 99.5%. Furthermore, even after conducting 10 repeated experiments, the separation efficiency remained consistently high at 96.1%.