AUTHOR=Romero-Montero A. , Rosas-Melendez S. A. , Valencia-Bermúdez J. L. , Nuñez-Tapia I. , Piña-Barba M. C. , Melgoza-Ramírez L. J. , Leyva-Gómez G. , Del Prado-Audelo M. L. 

TITLE=Oil/water separation by super-hydrophobic wastepaper cellulose-candelilla wax cryogel: a circular material-based alternative

JOURNAL=Frontiers in Materials

VOLUME=10

YEAR=2023

URL=https://www.frontiersin.org/journals/materials/articles/10.3389/fmats.2023.1308094

DOI=10.3389/fmats.2023.1308094

ISSN=2296-8016

ABSTRACT=<p><bold>Introduction:</bold> One of the most attractive fields for cellulose aerogels is water remediation, basically in the pollutant’s adsorption and oil/water separation. There are different sources to extract cellulose, but the extraction from paper waste is an excellent option for impulse circular materials applications.</p><p><bold>Methods:</bold> We obtained cellulose from office waste paper through a simple alkali method and used it to fabricate an aerogel by freeze-drying based on the materials’ circularity. To increase lipophilicity, the aerogel was modified using two different coatings: polycaprolactone (WOPP) and candelilla wax (WOPW), extracted from a Mexican plant. The aerogels were analyzed by several physicochemical techniques such as Scanning Electronic Microscopy, Infrared spectroscopy, and thermal analysis.</p><p><bold>Results and Discussion:</bold> To our knowledge, this is the first time that candelilla wax has been reported as aerogel modification. The highly porous aerogels showed a density of around 0.1 g/cm<sup>3</sup> and a fibrous structure. Furthermore, the contact angle of the aerogels was measured to compare the hydrophobicity of the surfaces, showing values around 120° in the modified aerogels compared with the hydrophilic behavior of pristine cellulose aerogel. The achieved recycled mineral oil absorption capacity for WOPW was 6.1 g/g, while for WOPP was 4.88 g/g. Thus, we obtained a natural coating aerogel with a high water/oil separation potential.</p>