Salt crystallization pressure as a new method to obtain micro and nanocellulose

• Published in: Cellulose (London) 2021-05, Vol.28 (7), p.4069-4087
• Main Authors: Nascimento, Sandra A., Scopel, Eupídio, Rezende, Camila A.
• Format: Article
• Language: English
• Subjects: Bioorganic Chemistry; Cellulose; Ceramics; Chemistry; Chemistry and Materials Science; Composites; Crystal growth; Crystallization; Elephant grass; Glass; Magnesium sulfate; Natural Materials; Organic Chemistry; Original Research; Physical Chemistry; Polymer Sciences; Shearing; Sodium sulfate; Sustainable Development
• ISSN: 0969-0239; 1572-882X
• DOI: 10.1007/s10570-021-03785-y

This work evaluated the crystallization pressure of sodium and magnesium sulphates as a tool to break down and defibrillate plant cell walls, aiming at a novel, environmentally friendly and low-cost methodology to obtain micro and nanofibrilated cellulose. Elephant grass leaves both in natura and delignified were soaked in Na 2 SO 4 and MgSO 4 solutions and oven-dried at 105 ± 3 °C to promote salt crystallization, while the damage resulted from the pressure exerted by the growing crystals within the cell walls was evaluated. Na 2 SO 4 crystallization proved to be more effective to unpack and defibrillate cell walls in comparison to MgSO 4 . In addition, both salts had more noticeable effects in previously delignified samples than in in natura samples . Nanofibrillated cellulose was obtained by Na 2 SO 4 action and after shearing fibres treated with an aqueous MgSO 4 solution (30% w/v), glycerol and NaOH (5% w/v). Graphic abstract