Construction of a Tannin-Based Polyphenol Network on the Surface of a Filter Paper and Its Adsorption Performance for Methyl Violet

An active hydroxymethyl group was introduced to the phenolic ring structure of tannin, and then the polyphenol network from hydroxymethyl tannin was immobilized on the surface of the filter paper (FP) by the reaction between hydroxymethyl tannin and cellulose of FP. Due to the introduction of the polyphenol structure on the surface of the FP, the ultraviolet absorption of the FP was broadened, the thermal stability of the FP was increased, and the FP was endowed with the antibacterial properties. The inhibition efficiency for Escherichia coli and Staphylococcus aureus was 82.3 and 80.1%, respectively. The FP-immobilized polyphenol network of tannin had good adsorption performance for methyl violet (MV), and the maximum adsorption capacity for MV was 131.5 mg·g–1. The adsorption efficiency could reach more than 98% when the initial mass concentration of MV was lower than 50 mg·L–1. The adsorption process conformed to the Langmuir isothermal adsorption model and quasi-secondary adsorption kinetic model. The FP-immobilized polyphenol network of tannin has good adsorption repeatability, and the preparation method is facile, green, and ecofriendly, which can be considered as a new potential adsorbent for dye wastewater.