[TG-fTIR study of the thermal-conversion properties of holo-cellulose derived from woody biomass].

Thermal-conversion properties of cellulose, hemi-cellulose and holo-cellulose derived from woody biomass were studied using TG-FTIR, and also compared to those of avicel cellulose and xylan. 3-D diffusion model was applied to calculate the kinetic parameters of thermal-conversion reaction of biomass materials, such as the activation energy, pre-exponential factors, etc, which showed good regression results. With the analysis of three-dimensional IR spectra of gas products, featured peaks of HzO, CO, CO2, CH4, and oxygenates were obviously observed where showing up with the maximum weight-loss rate in DTG curves. The possible forming routes of major gaseous products were analyzed and discussed. The order of releasing amounts for gaseous productions was approximately as CO2 > H2O > CO CH4. Based on the comprehensive understanding and comparative analysis of the whole results, it is concluded that the thermal conversion process of holo-cellulose was the result of interaction between cellulose and hemi-cellulose under the dominant role of cellulose.

[Analysis of pyrolysis process and gas evolution rule of larch wood by TG-FTIR].

The weight-loss character and gas evolution rule of larch wood at different heating rates were investigated by TG-FTIR (thermogravimetric analyzer coupled to a Fourier transform infrared spectrometer), and the results were compared with those of larch wood model-component mixture. The main weight-loss area of larch wood was wider than larch wood model-component mixture, and the residual char yield of larch wood (18.97%) was lower than larch wood model-component mixture (29.83%). During the pyrolysis process, the activation energy of larch wood model-component mixture was higher than the larch wood's in the low-temperature region, but there was little difference between the two segments in high temperature region. Larch wood came through several stages of water extraction, main component decomposition, charring during its pyrolysis process, and gas precipitation mainly happening at near 375 degrees C. The order of main gas products generated from the larch wood pyrolysis reaction was CO2 > H2O > CH4 > CO, and the gas product yield was significantly increased when the heating rate increased. The larch wood model-component mixture had the similar basic rules of producing gas to larch wood, but the former had relatively higher precipitation density than the latter.