Cellulose organic residue decomposition

Cellulose is the main carbohydrate utilized by termites that feed on wood or vegetable matter. The digestion in most species is brought about by flagellates that live in the intestines and secrete cellulase. The species that utilize organic residues do so very completely, and markedly hasten the decomposition processes. 

The fast pyrolysis decomposition of cellulose starts at temperatures as low as 150°C. Pyrolysis of cellulose below 300°C results in the formation of carboxyl, carbonyl, and hydro peroxide groups, elimination of water and production of carbon monoxide and carbon dioxide as well as char residue (Evans and Milne, 1987). Therefore low pyrolysis temperatures will produce low yields of organic liquid yields. Fast pyrolysis of cellulose, above 300°C, results in liquid yields up to 80 wt.%. Cellulose initially decomposes to form activated cellulose (Bradbury et al., 1979). Activated cellulose has two parallel reaction pathways, depolymerization and fragmentation (ring scission). The main products from each reaction pathway are rather different as ring scission produces hydroxyacetaldehyde, linear carbonyls, linear alcohols, esters, and other related products (Bradbury et al., 1979 Zhu and Lu, 2010 Lin et al., 2009) and depolymerization produces monomeric anhydrosugars, furans, cyclopentanones, and pyrans and other related products (Bradbury et al., 1979 Zhu and Lu, 2010 Lin et al., 2009). Each reaction pathway is independent and is influenced by pyrolysis temperature and residence time (Bradbury et al., 1979). 

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