Preliminary investigation into the use of amino-acid-derived ionic liquids for extracting cellulose from waste biomass to prepare cellulose aerogel adsorbents

To investigate the feasibility of cellulose extraction from lignocellulosic waste biomass using ionic liquids—a sustainable and efficient approach—for preparing cellulose aerogel adsorbents, we employed a fully green amino acid-derived ionic liquid, cysteine nitrate ([Cys][NO3]), for cellulose separation from diverse biomass sources. The extracted cellulose, with a purity range of 83.8-93.9%, was processed into cellulose aerogels (CAs) via a conventional aerogel preparation protocol. The resulting CA exhibited promising adsorption capacities, including 0.2-11.6 mg/g for Na+, 4.4-19.9 mg/g for Ca2+, 4.15-35.6 mg/g for Mg2+, and 1.85-13.3 mg/g for Cd2+, as well as 9.7-17.7 g/g for engine oil. These results demonstrate the presence of effective mass transfer channels in the CA, proving that the cellulose's fibrillation capacity was preserved in the pre-treatment. This study illuminates the potential of this green, straightforward method for preparing aerogels from cellulose derived from waste biomass, with promising applications in wastewater treatment and material recovery.