Preparation and properties of TiO2 superhydrophobic filter media modified by silane coupling agent KH570

Abstract

TiO2 sol was prepared by sol-gel method using tetrabutyl titanate as precursor and acetic acid as catalyst, and then hydrophobically modified TiO2 sol was obtained by reducing its surface energy with γ-methacryloxypropyl trimethoxysilane (KH570), the modified TiO2 sol was sprayed on the surface of the filter media to make it superhydrophobic. The wettability, surface morphology, chemical composition and filtration performance of the filter media before and after modification were analyzed.The results show that the modified coating is uniformly deposited on the surface of the filter media and the fiber surface completely wrapped, and the water contact angle of the modified filter media reaches 156.29°. By testing the filtration performance of the particles with the size of 0.3 μm at the filtration velocity of 0.043-0.127 m/s, it can be seen that the filtration efficiency of the modified filter media is increased by an average of 2.7672% compared with the unmodified filter media, and the filter quality factor is increased by 0.34%, which improves the filtration performance of the filter media. In addition, the hydrophobic filter media still has superhydrophobicity after 50 times of sandpaper abrasion cycles and 30 h acid-base solution immersion. The modified filter media has excellent self-cleaning performance by cleaning the surface of coal powder pollution.

Keywords

• tio2
• pet filter media
• silane coupling agent
• superhydrophobicity property
• filtration per-formance
• surface modification