蕲艾绒的热分析及热分解动力学研究  

Thermal Analysis and Thermal Decomposition Kinetics of Artemisia vulgaris L.

作　　者：徐文立 刘豪 宋红刚 刘建军 XU Wenli;LIU Hao;SONG Honggang;LIU Jianjun(Huanggang Meifeng Chemical Technology Co.,Ltd.,Huanggang 438011,China)

机构地区：[1]黄冈美丰化工科技有限公司,湖北黄冈438011

出　　处：《生物质化学工程》2024年第3期33-38,共6页Biomass Chemical Engineering

摘　　要：采用热重-微商热重(TG-DTG)技术研究了蕲艾绒在氮气气氛中的热分解行为及其非等温动力学,结果发现蕲艾绒的热分解过程分为两个阶段:第一阶段失重率为3.75%,主要为蕲艾绒中水分和少量挥发性油类物质的损失,第二阶段失重率为71.12%,主要为挥发性的油类物质和木质纤维物质的热分解。使用单重扫描速率法Achar微分方程和Coats-Redfern积分方程求出其动力学参数,得到了蕲艾绒热分解反应的控制机理函数,并利用多重扫描速率法的Kissinger方程、Flynn-Wall-Ozawa方程和Starink方程对其动力学参数进行验证,得到其热分解过程属于F_(3)(三级反应)机理控制,机理函数f(α)=0.5(1-α)^(3)、g(α)=(1-α)-2-1,表观活化能(E)为124.76 kJ/mol、指前因子(A)为5.78×10^(10)s^(-1),并确定蕲艾绒热分解非等温动力学方程为:dα/dt=(5.78×10^(10)/β)×(0.5×(1-α)^(3))×exp(-15006/T)。根据其热分解动力学参数进行估算,得出蕲艾绒在室温下的贮存期为4~5年。The thermal decomposition behavior and non-isothermal kinetics of Artemisia vulgaris L.in nitrogen were studied by thermogravimetric-differential thermogravimetric(TG-DTG)technique.The results showed that its thermal decomposition was divided into two-step process.In the first stage,the weight loss rate was 3.75%,which was mainly the weight loss of water and a small amount of volatile oil in A.vulgaris L..In the second stage,the weight loss rate was 71.12%,which was mainly the thermal decomposition of volatile oils and lignocellulose.Meanwhile,the kinetic parameters of A.vulgaris L.were obtained using the Achar differential equation and Coats-Redfern integral equation of the single scanning method,and its control mechanism function of the thermal decomposition was determined.The kinetic parameters were verified by Kissinger equation,Flynn-Wall-Ozawa equation and Starink equation of the multiple scanning rate method.It was found that the thermal decomposition process belonged to the F_(3)(third-order reaction)mechanism control,and the mechanism function f(α)=0.5(1-α)^(3),g(α)=(1-α)^(-2)-1.The apparent activation energy and the pre-exponential factor were 124.76 kJ/mol and 5.78×10^(10)s^(-1),respectively.The thermal decomposition non-isothermal kinetic equation of A.vulgaris L.was dα/dt=(5.78×10^(10)/β)×(0.5×(1-α)^(3))×exp(-15006/T).According to the estimation of thermal decomposition kinetic parameters,the shelf-life of A.vulgaris L.was 4-5 years at room temperature.

关 键 词：蕲艾绒 热分解 非等温动力学 贮存期 

分 类 号：TQ35[化学工程]