Pyrolysis, of cellulosic materials

Fred s major contributions were in the area of combustion and pyrolysis of cellulosic materials. At Montana, he developed a research program for unravelling the complex, consecutive and concurrent reactions involved in... 

M. Miura et al.. Microwave pyrolysis of cellulosic materials for the production of anhydrosugars. Journal of Wood Science, 47, 502-506 (2001). 

Although there has been a rapid decline in commercial destructive distillation of wood, manufacture of activated carbon by the pyrolysis of cellulosic materials still constitutes a major commercial operation. Finally, the possibility of developing new processes for production of special chemicals by the pyrolysis of cellulose, or the adaptation of the old process to the economy of developing nations blessed with rich forest resources, cannot be overlooked. Controlled pyrolysis of cellulose and cellulosic materials to provide a totally impermeable carbon and other industrial products is an example of the former possibilities. 

The pyrolysis of cellulosic materials results in the formation of highly volatile materials, a tarry distillate and a carbonaceous char. Early work (1909-10) by Klason [40,41] investigated... 

Source. Reprinted with permission from Shafizadeh F, Industrial pyrolysis of cellulosic materials, AppI Polym Symp, No. 28, 153-174, 1975. Copyright 1975, Elsevier. 

Celluloses.—Papers presented at a symposium on the thermal uses and properties of polysaccharides and lignins have discussed the pyrolysis of cellulosic materials. Phenols and carboxylic acids present in condensates of the smoke of cigarettes containing a cellulosic tobacco substitute have been identified and measured. The solubility of holocelluloses in DMSO—paraformaldehyde has provided the basis for a rapid laboratory method for predicting the dry-matter digestibility of cellulosic materials. The amount of dry matter solubilized by this chemical system correlated with that digested by rumen fluid in vitro or by cellulolytic bacteria. 

The subject of Figs. 4-6 involves another difficult topic the examination of carbonaceous materials. In order to obtain carbons prepared under controlled conditions, the pyrolysis of cellulose was studied. Fig. 4 shows just three of many spectra of pyrolysis sequences. The numerous changes in the spectra, e.g., the decline of aliphatic C-H stretching absorptions just... 

Shafizadeh, F. (1968). Pyrolysis and combustion of cellulose materials. Adv. Carbohydr. Chem. 23 419, 474. 

Vacuum pyrolysis results in rapid distillation of levoglucosan, and prevents further decomposition of this material. It has been shown that pyrolysis of cellulose in a nitrogen atmosphere proceeds at almost the same rate as pyrolysis under vacuum, but a lower yield of tar and a greater yield of the lighter fractions result, because of appreciable secondary reactions involving further decomposition of the intermediate fragments. ... 

The rate and kinetics of the thermal degradation of cellulosic materials have been investigated under a variety of conditions. However, these studies often relate to one of the physical effects produced by the overall process of heating or pyrolysis, instead of the kinetics of the individual chemical reactions involved. Consequently, the results are controversial and confusing. The variation of the results obtained under different conditions provides a vivid indication of the complexity of the reactions involved and the limited value of the overall kinetic data. 

---