Thermokinetic investigation of cellulose pyrolysis — impact of initial and final mass on kinetic results

Volker, Susanne; Rieckmann, Thomas

doi:10.1016/s0165-2370(01)00113-9

Cited by 85 publications

(51 citation statements)

References 13 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Fengel and Wegener, 1984;Völker and Rieckmann, 2002), that have a C content 15.8% greater than that of whole wood (Table 1, Figure 1). Under 2% O 2 , the higher reactivity of mangrove (evident in the isothermal TGA results; Figure 2), meant near -18 -complete loss of some samples at temperatures >500ºC.…”

Section: Mass Loss and %C Contentmentioning

confidence: 98%

Influence of production variables and starting material on charcoal stable isotopic and molecular characteristics

Ascough

Bird

Wormald

et al. 2008

Geochimica et Cosmochimica Acta

View full text Add to dashboard Cite

We present a systematic study on the effect of starting species, gas composition, temperature, particle size and duration of heating upon the molecular and stable isotope composition of high density (mangrove) and low density (pine) wood. In both pine and mangrove, charcoal was depleted in δ 13 C relative to the starting wood by up to 1.6‰ and 0.8‰ respectively. This is attributed predominantly to the progressive loss of isotopically heavier polysaccharides, and kinetic effects of aromatization during heating. However, the pattern of δ 13 C change was dependant upon both starting species and atmosphere, with different structural changes associated with charcoal production from each wood type elucidated by Solid State 13 C Nuclear Magnetic Resonance Spectroscopy. These are particularly evident at lower temperatures, where variation in the oxygen content of the production atmosphere results in differences in the thermal degradation of cellulose and lignin. It is concluded that production of charcoal from separate species in identical conditions, or from a single sample exposed to different production variables, can result in significantly different δ 13 C of the resulting material, relative to the initial wood. These results have implications for the use of charcoal isotope composition to infer past environmental change.

show abstract

Section: Mass Loss and %C Contentmentioning

confidence: 98%

Influence of production variables and starting material on charcoal stable isotopic and molecular characteristics

Ascough

Bird

Wormald

et al. 2008

Geochimica et Cosmochimica Acta

View full text Add to dashboard Cite

show abstract

“…The last one is important because a discrepancy in the amount of formed charcoal has been reported by other authors [8,9,12,14,15] when different heating rates are used.…”

Section: Introductionmentioning

confidence: 95%

“…This other kind of reaction rate expression was needed because the biomass shows a different behaviour when the heating rate varies along with time (or temperature), as the polymeric structure can both collapse or swell [8,9,14,15]. The parameter "c" is a correction factor to the cellulose decomposition when a variable heating rate is used.…”

Section: Kineticsmentioning

confidence: 99%

See 1 more Smart Citation

Autocatalytic kinetic model for thermogravimetric analysis and composition estimation of biomass and polymeric fractions

Cabeza

Sobrón

Yedro

et al. 2015

Fuel

View full text Add to dashboard Cite

A comprehensive kinetic model of slow pyrolysis of biomass during a Thermogravimetric analysis (TGA) has been developed, including the simulation of variable heating rates, composition estimation and structural analysis of biomass.Biomass was assumed as a matrix of three solid global components (hemicellulose, cellulose and lignin) in which water and oil can be also present.Kinetics were based on an auto-catalytic model because it can simulate the degradation in cellulosic materials, as the cleavage of the biopolymers produce oligomers that accelerate the further depolymerisation. The reaction pathway followed the Waterloo's mechanism, which stablishes that all solid compounds decompose into volatiles and charcoal. This mechanism was completed by the vaporization of water and oil, and assuming that the formed charcoal can break into volatiles by a slow reaction. The set was solved by the 8 th Runge-Kutta's method and validated by the Simplex Nelder-Mead and Broyden-Fletcher-Goldfarb-Shanno's methods. The development of this model has a high interest because it can help to understand how the conversion from biomass to biochemicals takes place.To assess what parameters can affect the thermal degradation of biomass pure polymeric samples of hemicellulose, cellulose and lignin and complex samples (seeds and woody biomass) were studied and fitted. Two types of operations were consideredtoo. An isothermal degradation from 150ºC up to 350ºC with increments of 50ºC, and a non-isothermal decomposition with heating rate of 5ºC/min, 10ºC/min and 20ºC/min up to temperatures around 800ºC, depending on the studied sample. Average absolute deviations lower than 7% were obtained. It was deduced that there are some interactions between the three main biomass compounds. These interactions were observed by the variations in the kinetic parameters between complex and pure 2 samples, also they were perceived between the isothermal and no-isothermal way. On the other hand, an effect of the biomass structure has been reported by the differences between the kinetics of the seeds and of the woody samples. It is remarkable that the developed model could reproduce the cellulose decomposition with a variable heating rate using a unique set of kinetic parameters. This was possible by a no-Arrhenius' dependence with temperature. In the same way, it was used to predict the initial composition of the studied biomass with deviations lower than 7% for lignin and cellulose.

show abstract

“…Antal and Várhegyi [4] reviewed the literature of cellulose pyrolysis and concluded that the pyrolysis of a small sample of pure cellulose is characterized by an endothermic reaction governed by a first order rate law with a high activation energy. Völker and Rieckmann [5] investigated the influence of the final mass on modelling results and evaluated the applicability of established kinetic models for engineering purposes.…”

Section: Introductionmentioning

confidence: 99%

Thermogravimetric analysis during the decomposition of cotton fabrics in an inert and air environment

Moltó

Font

Conesa

et al. 2006

Journal of Analytical and Applied Pyrolysis

View full text Add to dashboard Cite

The thermal degradation of samples of used cotton fabrics has been investigated using thermogravimetric analysis (TGA) between room temperature and 700 8C. Experiments were carried out with about 5 mg of sample in three different atmospheres: helium, 20% oxygen in helium and 10% oxygen in helium. Three different heating rates were used at each atmosphere condition. A kinetic model for the decomposition of used cotton fabrics explaining the behavior of all the runs performed has been proposed and tested. For the pyrolysis of the cotton, the model comprises two parallel reactions. For the combustion process, one competitive reaction was added to each parallel reaction of the pyrolysis model and four combustion reactions of the different solid fractions to obtain volatiles. One single set of parameters can explain all the experiments (pyrolysis, oxidative pyrolysis and combustion) at the three different heating rates used.

show abstract

Thermokinetic investigation of cellulose pyrolysis — impact of initial and final mass on kinetic results

Cited by 85 publications

References 13 publications

Influence of production variables and starting material on charcoal stable isotopic and molecular characteristics

Influence of production variables and starting material on charcoal stable isotopic and molecular characteristics

Autocatalytic kinetic model for thermogravimetric analysis and composition estimation of biomass and polymeric fractions

Thermogravimetric analysis during the decomposition of cotton fabrics in an inert and air environment

Contact Info

Product

Resources

About