Chiang Mai Journal of Science

 The quantitative relationship of important features of lignin chemistry and cellulose extraction performance (CEP) were studied through characterizing the chemical and structural properties of isolated lignin from ten straws and their celluloses. The syringyl/guaiacyl (S/G) and lignin/cellulose (L/C) ratios, and the CEP values were hence determined respectively upon Py-GC/MS and delignification selectivity. A significant correlation was observed in the studied straw samples between the CEP and the S/G ratio. By contrast, the L/C ratio showed a low correlation with the CEP. By 31P-NMR analysis, the CEP was found to exhibite a high positive correlation with the phenolic hydroxyl group in the isolated lignin compared to the aliphatic hydroxyl group, especially the free phenolic hydroxyl group, which, however, contributed less effect than the lignin S/G ratio to the CEP in terms of the correlation coefficient. The aliphatic hydroxyl group was hardly found to affect the CEP. These results indicate that the lignin S/G ratio is a most important parameter influencing cellulose extraction from straw.