7种果壳的热解特性及与主要组分相关性分析  

Pyrolysis Characteristics and Correlation Analysis with the Major Components of Seven Kinds of Nutshell

作　　者：蒋新元[1] 廖媛媛[1] 郭忠[1] 孟安[1] 黄泽才[1] 杨素文[1] 

机构地区：[1]中南林业科技大学材料科学与工程学院,长沙410004

出　　处：《林业科学》2015年第12期79-86,共8页Scientia Silvae Sinicae

基　　金：湖南省教育厅重点项目"林业剩余物定向催化热解制备富酚生物油及其调控机理研究"(13A119)

摘　　要：【目的】分析果壳的热解特性及与果壳中纤维素、木质素及半纤维素的相关性,为果壳类生物质的热化学转化利用提供基础数据。【方法】分析油茶壳、椰子壳、油桐壳、核桃壳、板栗壳、开心果壳和腰果壳的纤维素、木质素和半纤维素含量,并进行热重分析,同时分析7种果壳的热解失重峰值温度与果壳中纤维素、木质素和半纤维素含量的相关性。【结果】除腰果壳外,其他6种果壳的主要成分为纤维素、酸不溶木质素和半纤维素,三者总含量均在73%以上,腰果壳中纤维素、半纤维素和酸不溶木质素三者总含量仅为47.41%。除油桐壳以外,其他6种果壳在200~410℃温度范围均出现多个热解失重峰,椰子壳、油茶壳、开心果壳与腰果壳最高温热解失重峰的左侧出现明显的尖状热解失重峰,核桃壳和板栗壳则在最高温热解失重峰的左侧出现肩状热解失重峰。7种果壳的热解动力学模型符合一级动力学方程,热解活化能在40~85 k J·mol^(-1)之间。果壳的最高温热解峰峰值温度与果壳中木质素含量呈明显的正相关性(R=0.800,P=0.03<0.05),与纤维素含量的正相关性较弱(R=0.446,P=0.32>0.05),与半纤维素含量呈较弱的正相关性(R=0.509,P=0.24>0.05),与果壳中木质素和纤维素总含量的正相关性更显著(R=0.899,P=0.005<0.05)。7种果壳(除油桐壳外)左侧热解峰的峰值温度与半纤维素含量呈明显的正相关性(R=0.836,P=0.04<0.05),与木质素含量呈弱的正相关性(R=0.484,P=0.33>0.05),而与纤维素含量的正相关性更弱(R=0.295,P=0.57>0.05)。【结论】7种果壳中纤维素、木质素与半纤维素含量不同,各具有不同的热解特性,其最高温热解峰峰值温度主要受果壳中木质素含量的影响,而其左侧热解峰峰值温度主要受果壳中半纤维素含量的影响。[ Objective ] Nutshells are important forest biomass resources for energy in China. In order to provide theoretic supports for the thermal conversation and utilization of nutshells,the pyrolysis characteristics of nutshells and the correlations of cellulose,hemicellulose and lignin were investigated in this study. [ Method] The cellulose, hemicellulose and lignin contents of seven kinds of nutshells, including Camellia shell, Coconut shell, Tung shell, Walnut shell, Chestnut shell, Pistachio shell and Cashew nut shell, were measured. Using the thermogravimetric analysis the correlations between pyrolysis peak temperature and the cellulose, hemicellulose and lignin content of nutshells were also analyzed. [ Result ] The major components of the six kinds of nutshell except Cashew nut shell are cellulose, lignin and hemicellulose, and the total content of these three components is more than 73% , while the total content of that in Cashew nut shell is only 47.41%. Several mass loss peaks are observed on temperature range from 200 to 410℃ during the whole pyrolysis process for six kinds of nutshells except Tung shell. Obviously pointed pyrolysis peaks on the left of the maximum pyrolysis peaks are appeared for Coconut shell, Camellia shell, Pistachio shell and Cashew nut shell, while for Walnut shell and Chesnut shell, acromion pyrolysis kinetic equations ranged in 40 - 85 of all seven kinds of nutsh pe ell kJ.mol-1 The correlation b aks on the left of the maximum pyrolysis peaks are found. The pyrolysis s meet first-order kinetic equation, and the pyrolysis activation energy is etween the maximum pyrolysis peak temperature and the lignin content ofnutshells is significantly positive （R = 0. 800, P = 0.03 〈 0.05 ） , the correlation between the maximum pyrolysis peak temperature and the cellulose content of nutshells is weakly positive （R = 0. 446, P = 0.32 〉 0.05 ）, and that between the maximum pyrolysis peak temperature and the hemicellulose content of nutshells is weakly positive too （R = 0. 509, P=0

关 键 词：果壳类生物质 热解 组分分析 热重分析 相关性分析 

分 类 号：TK6[动力工程及工程热物理—生物能]