在纤维素上负载K2 SO4和K2 CO3,采用热重-红外联用(TG-FTIR)对负载钾盐的纤维素与煤共热解特性进行了研究,并采用红外光谱表征了热解前后样品的化学结构.结果表明:在900℃热解后,焦样中含C,H,O有机官能团和高岭石的峰消失,其中有机官能团的消失与气体产物释放有关,高岭石的消失是由于热转化生成偏高岭石和石英.纤维素与煤共热解过程中发生了协同反应.钾盐的添加对共热解反应中焦炭产率、最大反应速率、反应温度区间和活化能等都有较大影响,还促进了CO和CO2的产量增加,并且使它们产生的温度区间移向低温区,其中K2 CO3的作用更明显.K2 SO4对酸类和酮醛类等含C—O官能团的产物生成具有促进作用,而K2 CO3具有抑制作用.钾盐对共热解CH 4气体的生成有不同程度的抑制作用.%K2 SO4 or K2 CO3 was loaded on a microcrystalline cellulose material.The co-pyrolysis characteristics of cellulose loaded with catalyst and coal were investigated by TG-FTIR, and the chemical structure of the samples before and after pyrolysis at 900 ℃ was characterized by FTIR.The FTIR results show that the absorption peaks of carbon-containing,hydrogen-containing and oxygen-containing functional groups and kaolinite disappear after pyrolysis at 900 ℃.The disappearance of organic functional groups is due to the release of gaseous products.The change of kaolinite is caused by thermal transformation into metakaolinite and quartz.Synergistic effect is observed during the co-pyrolysis of cellulose and coal.The load of potassium salt has a great influence on the char yield,the maximum reaction rate,the reaction temperature range,and the activation energy during the co-pyrolysis.The presence of potassium salt also results in an increase in CO and CO2 yields.Moreover,the temperature ranges of CO and CO2 generation shift to lower temperatures with the addition of potassium salt,particularly the K2 CO3 .In addition, K2 SO4 has a positive effect on the evolution of products containing C—O functional groups such as acids and ketals,while K2 CO3 has a negative effect on it.K2 CO3 and K2 SO4 have different extent of negative effect on the release of CH 4 .
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