the percentage weight loss of CA, produced from cotton linters, had been reduced by increasing the sulfuric acid concentration from 10% to 30% (Fig. 6B). Also, sulfuric acid (30%) gave a lower weight loss (1.84%) of CA produced from cotton linters than that (2.92%) from flax fibers. These results could be due probably to the high stability of chemical crystalline structure and ponding of CA from cotton linters.