Related content on wood and its thermal analysis

The reaction system has obvious thermal effect, which is confirmed by thermal analysis of the components of the technical materials, which is due to the violent thermal decomposition of the components of the technical materials. The extraction process model, the physical dissolution of low molecular substances in the technical materials is carried out at less than 120 ℃.

The semi-continuous non-isothermal dynamic extraction experiment of wood was carried out on a German-made solid material supercritical fluid extraction device. The whole device can be divided into three parts: solvent supply system, material extraction system and product processing system. Determination of cable content using 205nfl UV spectrophotometry.

The thermal analysis experiment of wood and its components was carried out on a PCT-1 differential thermal balance (manufactured by Beijing Optical Instrument Factory), the heating rate was 10C/min, the sample mass was about 5nag, and the atmosphere was still air.

Thermal effect of extraction process The experiment was done on a solid material supercritical fluid extraction device made in Germany. Non-isothermal technology was used in the experiment process, the heating rate was kept constant, and it had a good temperature control system. However, during the experiment, it was found that, In the region of 320-360℃, the heating rate is not very stable, and sometimes it is not easy to control at all, and there is an abnormal phenomenon that the temperature rises rapidly and then falls back slowly, which indicates that in this temperature range, the reaction system has obvious thermal effects.

For absolute ethanol extraction, the exothermic peak temperature is 355-359 ℃, with the increase of pressure, the duration tends to be shortened. When extracting with aqueous ethanol, the exothermic peak temperature moves forward, such as when the mole fraction of water is 0.22 When , the exothermic peak temperature is 340 °C; when the mole fraction of water is 0.39, the exothermic peak temperature is 306 °C, and the duration is also shortened. When thermal phenomena occur, both the extraction rate and the gas generation rate have corresponding maxima.

The above experimental phenomenon can be scientifically and reasonably explained by the results of the differential scanning calorimetry (osc) analysis of the wood. The wood has a heat flow peak in the range of 214-415qC, the thermal effect value is 5.2kJ/g, and the maximum heat flow temperature is 341qC. The hot bee temperature is 340359qC, which is in good agreement with the DSC analysis data of wood. It can be seen that almost all wood and its various components have obvious exothermic effects in the region of 300 360 qC, which is consistent with the Dsc curve of wood in still air atmosphere in Figure 1.