水葫芦催化热解动力学特性

Characteristics of Catalytic Pyrolysis Kinetics of Water Hyacinth

利用热重法对吸附了重金属盐CuSO_4的水葫芦(WH)热解特性及反应动力学进行研究,考察重金属Cu^(2+)在水葫芦热解过程中的催化作用,同时采用Coats-Redfern法根据热重曲线对催化热解过程进行拟合计算获得水葫芦热解的活化能和指前因子等动力学参数来建立动力学模型。热重分析结果表明:Cu^(2+)对水葫芦热解过程有明显的催化作用,随着Cu^(2+)浓度的增大,水葫芦热解最大失重率明显增大,在Cu^(2+)浓度为0.5%时达到最大值为96.26%,相比于水葫芦单独热解提高了32.92%。动力学分析表明:可以用一级反应来描述水葫芦热解过程;当Cu^(2+)浓度为0.5%时,水葫芦主要组分热解的活化能均有所下降。因此,Cu^(2+)浓度为0.5%时对水葫芦热解过程最有利。

The properties and reaction kinetics of water hyacinth（WH） were investigated using thermogravimetric method, and catalysis of heavy metal Cu2＋ on pyrolysis of WH was also investigated. Matching computation was carried out to analyze catalytic pyrolysis of WH with the Coats-Redfern method, through which the apparent activation energy and pre-exponential factors of WH with different Cu2＋ contents were obtained. Thermogravimetric analysis results showed that Cu2＋ had obvious catalytic effect on the pyrolysis of WH. The maximum weight loss rate of WH was significantly increased with the increase ofCu2＋ concentration. When the Cu2＋ concentration was 0.5 %, the maximum weight loss rate of WH reached the maximum value of 96.26 %, which was increased by about 32.92 % compared with that of WH with no Cu2＋ content. The kinetic analysis shows that the first order reaction can be used to describe the process of WH pyrolysis. When the Cu2＋ concentration was 0.5 %, the apparent activation energy for main components of water hyacinthwas decreased in pyrolysis. Therefore, the Cu〉 concentration of 0.5 % was the most favorable for the pyrolysis of WH.