Biobased Aerogels Fabricated by the Ice Crystal Method for Smoke Purifying

Filters play a crucial role in smoke filtration. However, conventional cigarette filters lack degradability or high filtration capacity. Developing cigarette filters with low cost, degradability, and desirable filtration efficiency is an urgent requirement in the cigarette market. In this study, biobased composite aerogels with hierarchically porous structure for cigarette smoke are fabricated. The prepared aerogels consist of naturally biocompatible materials; the microfibrillated cellulose and poly(vinyl alcohol) endow the composite aerogels with mechanical robustness and flexibility. In addition, tannic acid not only has the effect of trapping toxic chemicals in smoke but also performs an antibacterial function in collaboration with the fabricated TTA-Alg polyelectrolyte. It is believed that the hierarchically porous structure of the biobased aerogels induced by the ice template method facilitates the adequate flow of the smoke in aerogels, resulting in high purification efficiency and a relatively constant pressure drop during the smoke filtration process, which is conducive for smoke purification. The prepared aerogel could efficiently capture toxic chemicals in smoke, including filtering 96.58% of oil smoke, 88.64% of total nonmethane hydrocarbons, and 94.79% of particulate matter, exhibiting higher removal efficiency than commercial cigarette filters. In brief, the designed biobased aerogels possess low cost, environmental friendliness, compressibility, and desirable smoke filtration efficiency, showing a promising application prospect for smoke filtration.