茶梗的热解特性及动力学研究  

Thermal Decomposition Characteristics and Kinetics of Tea Stalk

作　　者：郭先华[1] 张建育 湛方栋[1] 何永美[1] 李博[1] 蒋明[1] GUO Xianhua;ZHANG Jianyu;ZHAN Fangdong;HE Yongmei;LI Bo;JIANG Ming(College of Resources and Environment,Yunnan Agricultural University, Kunming 650201, China)

机构地区：[1]云南农业大学资源与环境学院,云南昆明650201

出　　处：《林产化学与工业》2018年第2期119-125,共7页Chemistry and Industry of Forest Products

基　　金：国家自然科学基金资助项目(41461117;51768074);云南农业大学科研启动基金项目(A2002350)

摘　　要：为综合利用茶梗废弃物,采用同步热重-差热分析法(TG-DTA)研究了茶梗的热解过程及动力学。结果表明:在氮气气氛下不同升温速率茶梗样品的TG-DTG-DTA曲线中,茶梗的热失重过程可分为5个阶段,主分解反应发生在第三、四阶段,在4种不同的升温速率(10、15、20和25 K/min)下,这两个阶段的平均失重率分别为55.12%和28.48%,且均表现为放热过程;随着升温速率的增大,第四阶段分解反应向高温区域移动。采用Kissinger法、FWO峰值转化率近似相等法、FWO等转化率法分别计算了茶梗的热解动力学参数。结果显示:Kissinger法和FWO峰值转化率近似相等法更适用于动力学参数的求解,两种方法得到的表观活化能分别为666.53和642.80 kJ/mol;Kissinger法计算得到的指前因子对数值lnA=145.83。In order to provide comprehensive utilization of tea stalk waste by thermochemical conversion, the thermal decomposition process of tea stalk and its kinetics were studied with simultaneous measurements of thermogravimetry（ TG）/differential thermal analysis（ DTA）. The TG-DTG-DTA curves of tea stalk were acquired in a nitrogen atmosphere. The results indicated that the mass loss process of the samples could be divided into five stages. Among the five stages,most of the decomposition occurred in the third and fourth stages. The two main stages were indicated as exothermic processes,with the average weight loss rates of 55. 12% and 28. 48% at different heating rates of 10,15,20,25 K/min,respectively. At higher heating rate,the fourth stage of the decomposition reaction was shifted to higher temperature range. The thermal decomposition kinetic parameters were calculated by Kissinger,FWO peak maximum evolution and FWO isoconversional methods. The results showed that the Kissinger and FWO peak maximum evolution methods were more suitable for the thermal decomposition kinetic parameters. The apparent activation energies were calculated to be 666.53 and 642.80 kJ/mol by the two methods,respectively.And natural logarithm of the pre-exponential factor（ ln A） calculated by Kissinger method was given as 145.83.

关 键 词：茶梗 热解 动力学 氮气气氛 

分 类 号：TQ35[化学工程] S216.2[农业科学—农业机械化工程]