Pyrolysis of cellulose

Organic matter declines through pyrolysis pyrolysis of cellulose... 

SCHEME 32. Anhydro sugars obtained by pyrolysis of cellulose. 

J. Piskorz, P. Majerski, D. Radlein, A. Vladars-Usas, and D. S. Scott, Flash pyrolysis of cellulose for production of anhydro-oligomers, J. Anal. Appl. Pyrol., 56 (2000) 145-166. 

D. Fabbri, C. Torri, and V. Baravelli, Effect of zeolites and nanopowder metal oxides on the distribution of chiral anhydro sugars evolved from pyrolysis of cellulose An analytical study, J. Anal. Appl. Pyrolysis, 80 (2007) 24-29. 

C Solid State NMR. Earlier workers have used 13 C solid state NMR to monitor char formation during the pyrolysis of cellulose (18). They found the 13C NMR of cellulose heated at progressively higher temperatures shows the loss of aliphatic carbons and the appearance of small broad new resonance peaks at... 

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... 

The synthesis started with levoglucosenone 4, available by the pyrolysis of cellulose, e.g. old newspapers. Bromination-dehydrobromination gave the enantiomerically-pure Diels-Alder dienophile 5, which was combined with isoprene to give predominantly the crystalline adduct 1. Hydrolysis and acetylation led to 6, which was carried on to the geometrically-defined allylic alcohol 7 via reduction with Zn-Cu couple. Overman rearrangement of 7 proceeded with high facial control, to give 8. 

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... 

In the area of waste utilization, Fred s program on the heat content, gasification, and carbonization of forest fuel is now recognized as a major step in our understanding of forest fires. The acid-catalyzed pyrolysis of cellulosic waste to afford l,6-anhydro-3,4-dideoxy-)3-D-g/ycero-hex-3-enopyranos-2-ulose ( levoglucosenone ) pointed the way to another method of chemical conversion of cellulosic wastes similar to cat-cracking in the petrochemical industry. 

McGrath, T. E., Chan, W. G., and Hajaligol, R. (2003). Low temperature mechanism for the formation of polycyclic aromatic hydrocarbons from the pyrolysis of cellulose. J. Anal. Appl. Pyrolysis 66,51-70. 

At higher temperatures, the intermediates, including levoglucosan and the condensation products further pyrolyze to give various products by fission of the carbohydrate units and rearrangement of the intermediate products. Table III shows the products obtained from the pyrolysis of cellulose and treated cellulose at 600° (8). The significant increase in the yields of water and char and decrease in the yield of tar in the acid treated cellulose verifies the previously mentioned promotion of dehydration and charring reactions by acidic additives. 

On the basis of this observation, the pyrolysis of mixtures of cellulose (1) and various vegetable oils under a variety of conditions was studied, and we have developed a convenient method for converting cellulose (1) to levoglucosenone (2) in >10% yield.6 The previously reported7 yields of levoglucosenone (2) produced by the pyrolysis of cellulose (1) under acidic conditions are usually 2-5% and utilize special vessels and procedures that are more involved than ours. Our procedure is essentially a vacuum distillation. 

A.A. Faroq, D. Price, G.J. Milnes, and A.R. Horrocks, Use of GC analysis of volatile products to investigate the mechanisms underlying the influence of flame retardants on the pyrolysis of cellulose in air. Polym. Degrad. Stab., 33, 155-170 (1991). 

Essig M, Richards GN, Schenck E. Mechanisms of formation of the major volatile products from the pyrolysis of cellulose. In Schuerch C, editor. Cellulose and wood - chemistry and technology. Syracuse, NY Wiley Sons 1988. p. 841-62. 

Richards GN. Glycolaldehyde from pyrolysis of cellulose. J Anal Appl Pyrolysis. 1987 10 251-5. 

Pyrolysis as defined is a process of thermal decomposition occurring in the absence of oxygen. Pyrolysis of biomass is a complicated multistage reaction for which many pathways and mechanisms have been proposed.551-558 The best known is the model developed by Broido and Shafizadeh559,560 for pyrolysis of cellulose that can be also applied, at least qualitatively, to whole biomass (Fig. 33.30). 

Halpern, Y., Riffer, R., and Broido, A., Levoglucosenone (l,6-Anhydro-3,4-Dideoxy-Delta3-Beta-D-Pyranosen-2-One) - Major product of acid-catalyzed pyrolysis of cellulose and related carbohydrates. J Organic Chem 1973, 38 (2), 204-209. 

Diebold, J. P., A unified, global-model for the pyrolysis of cellulose. Biomass Bioenergy 1994, 7 (1-6), 75-85. 

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