碱金属盐对生物质三组分热解的影响

研究碱金属盐的添加对生物质热解的催化机理。以生物质的主要有机组分(半纤维素、纤维素和木质素)为研究对象，采用热重分析仪对生物质三组分及添加碱金属盐后(KCl、K2CO3和Na2CO3)的热解行为进行试验研究，并采用一级反应对其热解动力学进行计算分析。试验结果表明KCl和Na2CO3的添加对生物质三组分热解的催化作用不明显，而K2CO3对半纤维素和纤维素热解均有明显的促进作用，使他们的热解温度降低，且随着K2CO3添加量的增加，催化作用逐渐增强；对于半纤维素、纤维素与木质素合成的生物质的热解而言，K2CO3的加入使得纤维素和半纤维素的热解失重峰重合；同时K2CO3的添加对木质素的高温热解也有积极的影响。

Influence of Alkali Salts on the Pyrolysis of Biomass Three Components

Catalytic mechanism of alkali salts addition on biomass pyrolysis was researched. The main organic components (hemicellulose, cellulose and lignin) were involved in as model biomass samples. The pyrolysis behavior of biomass was investigated using thermogravimetric analyzer with alkali salts (KCl, K2CO3 and Na2CO3) addition, and the kinetics was calculated using Coats-redfern method with first order reaction. The result show that the catalytic variant with alkali salt type as the addition of KCl and Na2CO3 don’t display obvious influence on the pyrolysis of biomass components, while K2CO3 show great catalytic and shifted the pyrolysis of hemicellulose and cellulose to lower temperature. Furthermore, it increased with the addition amount increasing. Regards to synthesis biomass, the degradation of hemicellulose and cellulose is overlapped with K2CO3 addition. The addition of K2CO3 also showed great favorable influence on lignin pyrolysis at higher temperature.