生物油及其重质组分的热解动力学研究

KINETICS OF PYROLYSIS OF BIO-OIL AND ITS HEAVY FRACTIONS

采用热重分析法对生物油及其三种重质组分模型化合物的热解特性进行了对比研究,并对动力学参数进行了求解。结果表明:生物油的热解包括挥发组分的蒸发及重质组分的裂解两个阶段,反应级数都是4级,活化能分别为29～36kJ/mol及13～19 kJ/mol;三种重质组分模型化合物中左旋葡聚糖也存在两个失重区间,反应级数分别为1和2,且表观活化能最高;3,4二甲氧基苯甲醛和丁香酚则只有一个失重区间,且相应的反应级数分别为0.8和0.5,表观活化能也依次降低。

The pyrolysis behaviors and kinetics of bio-oil and its model compounds of heavy fractions （Eugenol, Levoglucosan and 3,4-Dimethoxybenzaldehyde） are studied by thermogravimetrie （TG） analysis. The curves of TG and corresponding DTG are analyzed. The results show that the pyrolysis of bio-oil consists of two stages, that is, the evaporation stage of volatile fractious and the decomposition stage of heavy fractions. Both of the two stages are four-order reactions, whereas their activation energy are 29-36 kJ/mol and 13-19 k J/mol, respectively. Among three model compounds of bio-oil heavy fractions, there are two stages in the pyrolysis process of levoglucosan with different reaction order of land 2; while there are only one stage in that of 3,4-Dimethoxybenzaldehyde and Eugenol, with different reaction order of 0.8 and 0.5, respectively. The order of the activation energy of these compounds are that levoglucosan 〉 3,4-Dimethoxybenzaldehyde 〉 Eugenol.