The preparation of porosity modified porous organic frameworks via kaolin loading and its improved aromatic organic compounds removal performance

Porous organic framework material (PAF-45) with a wholly aromatic framework, intrinsic microporosity and pi-pi conjugation system is used in aromatic pollutant removal. Here, we synthesized a new type of organic porous material (PAF-45/KAL), that was doped with Kaolin during the synthesis of PAF-45. The composite material possesses better performance in adsorption and photocatalytic degradation of aromatic organic compound (AOC) than that of PAF-45. The Kaolin doping changes the polymerization method of PAFs, that turn random polymerization into more fixed-position polymerization. Because of the variation of polymerization method, PAF-45/ KAL's pore structure got effectively changed. The composite has not only original micropores but also more mesoporous structure compared with PAF-45. In the static adsorption experiments under room temperature and pressure, PAF-45/KAL could uptake 10-50% more AOC than PAF-45, for example, 50% more for chlorobenzene. Moreover, the photocatalytic ability of PAF-45/KAL gets promoted under visible light illumination, that it could decompose same amount of colorless aniline in shorter time. More importantly, owing to the clay is natural mineral, doping with Kaolin to improve porous organic materials' performance is a low-cost and environmental method.

Automated summary

PAF-45/KAL, a novel organic porous material doped with Kaolin, exhibits enhanced adsorption and photocatalytic degradation properties compared to PAF-45 due to the change in polymerization method and resulting alteration in pore structure. The composite material not only retains original micropores but also contains more mesoporous structure, enabling it to uptake more AOC and exhibit improved photocatalytic ability under visible light illumination. The use of natural mineral clay Kaolin as a dopant for enhancing porous organic materials presents a cost-effective and environmentally friendly method.