Characterizations and great application potential for air filtration of konjac glucomannan/curdlan aerogels

The pore size distribution and pore number had a great impact on the air filtration performance of polysaccharide-based aerogels. In this study, konjac glucomannan (KGM)/curdlan (KC) aerogels were prepared by the vacuum freeze-drying method, and the microstructure, molecular interaction, mechanical property, thermal stability, and air filtration performance were investigated. Results indicated that KGM and curdlan showed good compatibility based on hydrogen bonds and formed complete aerogel with three-dimensional network structure. KC1.2 displayed the highest compressive stress and thermal stability. With the addition of curdlan, the pore size decreased and the pore number increased, which resulted in the improvement of filtration efficiency. However, the high number (up to 1200) of pores in KC1.2 caused a decrease of filtration efficiency, and KC1.2 showed high air resistance (up to 1000 Pa). For PM1.0 and PM2.5, all KC aerogels had high filtration efficiency of more than 80 %. Considering the filtration efficiency and air resistance, KC0.9 was regarded as the optimum material for air filtration. All KC aerogels maintained stable filtration efficiency and pore structure after fifteen filtration cycles, demonstrating a long service life. These results indicated that KC aerogel had great potential for application in air filtration.