生焦是制备高纯石墨主要原料之一,对其热解脱硫特性进行动力学研究。在氩气气氛下,利用TG-DSC联合法对样品进行热重差热扫描分析,采用差减微分（Freeman-Carroll）法对样品的热解数据进行处理。结果表明,添加Na2CO3生焦热解过程可分为3个阶段,第一阶段为试样脱吸附水的过程,脱水温度360~456K,质量减少1.92%;第二阶段为生焦热解脱硫的主反应阶段,反应温度783~1 174K,质量减少16.86%;第三阶段为残余物的分解过程。热解最终产物为炭和硫化钠。添加Na2CO3后生焦脱硫率提高,其表观活化能E为157.12 kJ/mol,指前因子A为5.4×10^8 min^-1,反应机理函数为f（α）=（1-α）^6.13。
Coke is one of production of high purity graphite. The desulfurization kinetics characteristics of coke were studied. At Ar atmosphere, the differential thermal analysis of sample was studied by the TG-DSC method. The dynam- ics parameters of the coke pyrolysis reaction were calculated by Freeman-Carroll method depending on the TG-DSC curves. The experimental results showed that coke pyrolysis process could be divided into three phases. At the first phase, the free water of the sample was removed, the dehydration temperature was 360-456 K and the weight loss was 1.92%. At the second phase, the main reaction was the raw coke pyrolysis desulfurization reaction, the reaction temper- ature was 783~1 174 K and the weight loss was 16.86%. At the third stage, the residue was decomposed. The final product was carbon and sodium sulfide. The desulfurization rate of coke increased when adding NazCO3, whose the ap- parent activation energy E was 157. 12 kJ/mol, the pre-exponential factor A was 5.4~ 10^8 min ^-1, and reaction mecha- nisms function was f （α） = （1-α）^6.13.
Journal of Wuhan University of Technology