Dilute Alkali and Hydrogen Peroxide Treatment of Microwave Liquefied Rape Straw Residue for the Extraction of Cellulose Nanocrystals

Figure 3

SEM images of liquefied residues from different liquefactions and chemical treatments: (a) raw rape straw; (b) 140°C/15 min; (c) 160°C/15 min; (d) 180°C/7.5 min; (e) 180°C/10 min; (f) 180°C/15 min; (g) 2% NaOH for 1 h; (h) 5% H₂O₂ for 5 h (other liquefaction conditions: methanol/rape straw, 6/1; sulfuric acid, 3%).

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