氯化铁对高硫石油焦-CO_2气化的催化作用

Catalytic Activity of Ferric Chloride for High-Sulfur Petroleum Coke-Carbon Dioxide Gasification

以FeCl3为催化剂,采用热天平考察了FeCl3添加量、气化温度、FeCl3添加方法对高硫石油焦-CO2气化反应转化率和气化反应速率的影响,采用4种动力学模型对石油焦-CO2催化气化动力学曲线进行拟合,并对石油焦催化气化残渣进行XRD分析。结果表明,高硫石油焦催化气化反应速率随气化温度、FeCl3添加量的增加而增大,随转化率的增加而减小,与非催化石油焦气化的单峰动力学曲线不同;采用离子交换法添加FeCl3比采用浸渍法的催化气化效果好。FeCl3催化石油焦-CO2气化反应初始阶段,铁主要以Fe3C形式存在,随着反应的进行大部分Fe3C与石油焦中的S结合形成FeS,导致催化剂活性降低。4种动力学模型拟合结果表明,随机孔模型效果最好,相关系数在0.96以上。

FeCl3 was used as a catalyst for high-sulfur petroleum coke-CO2 gasification. The gasification reactivity of petroleum coke with different FeCl3 loadings and loading methods was examined by using a thermogravimetric analyzer. Four kinetic models were used to fit the kinetic curve for catalytic gasification of petroleum coke. The residue of catalytic petroleum coke-CO2 gasification was analyzed by XRD. The results showed that the gasification rate of petroleum coke increased with increase of FeCl3 loadings within the experiment range, and decreased with the increase of conversion in whole course of catalytic gasification, which is different from the single- peak kinetic curve of non-catalytic petroleum coke-CO2 gasification. In catalytic petroleum coke-CO2 gasification, the catalytic activity of FeCl3 loaded by ion exchange method was higher than that by impregnation method. At the initial stage of gasification the precipitated iron existed as Fe3C, which quickly reacted with S in petroleum coke to form FeS, leading to the catalytic activity loss. The random pore model described well the kinetic curve for catalytic gasification of petroleum coke among the four kinetic models, whose correlation coefficient exceede 0.96.