Feasibility for the preparation of aerogels with celluloses extracted mildly from waste palm leaves

Abstract Reasonable use and disposal of agricultural and forestry wastes become an urgent focus of attention with the dangers of pollution and squandering. In this paper, palm leaves, a typical kind of cellulose-rich agricultural and forestry waste, were attempted to prepare high-valued porous aerogels with cellulose by a short and mild extraction followed by the process of cross-linking with polyvinyl alcohol (PVA). Scanning electron microscope (SEM), Fourier transform-infrared (FTIR), X-ray diffraction (XRD), Bruno-Emmett-Teller (BET), and thermogravimetric analysis (TGA) were applied to examine their structures, chemical composition, and performance compared with hardwood cellulose aerogels. The results showed that palm leaf cellulose could be extracted friendly under mild extraction of 5% NaOH solution for 7 h, following 10% H2O2 solution for 8 h at 80 °C, which inhibits effectively the alkaline hydrolysis of cellulose with the extraction rate of 35.25%, the cellulose purity of 87.12%, and crystallinity of 69.9%. Compared with hardwood cellulose aerogel, the prepared environmentally friendly and recyclable palm leaf cellulose aerogel is a promising application material with similar ultra-low density, high porosity, specific surface area, thermal stability, and better compression resilience, which provides a new technical direction for the high-value application of agricultural and forestry wastes.