Construction of a\nTannin-Based Polyphenol Network\non the Surface of a Filter Paper and Its Adsorption Performance for\nMethyl Violet

An active hydroxymethyl group was introduced to the phenolic\nring\nstructure of tannin, and then the polyphenol network from hydroxymethyl\ntannin was immobilized on the surface of the filter paper (FP) by\nthe reaction between hydroxymethyl tannin and cellulose of FP. Due\nto the introduction of the polyphenol structure on the surface of\nthe FP, the ultraviolet absorption of the FP was broadened, the thermal\nstability of the FP was increased, and the FP was endowed with the\nantibacterial properties. The inhibition efficiency for Escherichia coli and Staphylococcus\naureus was 82.3 and 80.1%, respectively. The FP-immobilized\npolyphenol network of tannin had good adsorption performance for methyl\nviolet (MV), and the maximum adsorption capacity for MV was 131.5\nmg·g<sup>–1</sup>. The adsorption efficiency could reach\nmore than 98% when the initial mass concentration of MV was lower\nthan 50 mg·L<sup>–1</sup>. The adsorption process conformed\nto the Langmuir isothermal adsorption model and quasi-secondary adsorption\nkinetic model. The FP-immobilized polyphenol network of tannin has\ngood adsorption repeatability, and the preparation method is facile,\ngreen, and ecofriendly, which can be considered as a new potential\nadsorbent for dye wastewater.