【摘要】 利用热重仪研究浸渍不同K含量生物质(WB)样品的热解和加氢热解过程,以明确K+对生物质热解行为及动力学参数的影响。结果表明,K+对生物质热解及加氢热解均有较强的催化作用,其催化作用的强弱与K含量有关。K+浸渍对生物质热解行为及其特征参数(热解峰温TP、最大失重速率、焦产率等)均有重要影响。K+浸渍使生物质热解峰温提前,在H2中热解时这种效应更加明显。同时K+浸渍使焦产率显著增大,主要是由于K+促进了缩聚成焦反应。动力学分析表明,生物质热解可用两个一级反应来描述。ln A随E变化呈良好线性,表明生物质热解及加氢热解时均存在动力学补偿效应(KCE)。更多还原

【Abstract】 Pyrolysis and hydropyrolysis processes of biomass(WB) samples impregnated with different potassiumcontents were investigated using a thermogravimetric analyzer to determine the influence of potassium on their pyrolysisbehavior and kinetic parameters. The results indicated that potassium can catalyze biomass pyrolysis and hydropyrolysissignificantly,but this ability is related to the potassium content. The impregnation of potassium has significant effect onthe pyrolysis behavior and characteristic parameters,such as the temperature at which the maximum degradation rateoccurs(Tp),the maximum degradation rate and char yield. The Tp values shift to lower temperature after impregnatingpotassium,and this effect is more prominent when the biomass is pyrolysized under H2 atmosphere. Moreover,theapparent increase of char yield is found for all K-impregnated samples,which is mainly due to the fact that potassium canfacilitate the polycondensation reaction for char formation. According to the kinetic analysis,the pyrolysis of the biomasscan be described as two first-order reactions. The remarkably linear relationships between ln A and E for biomass pyrolysisunder both N2 and H2 atmosphere indicate the existence of a kinetic compensation effect(KCE).更多还原