拜耳法赤泥催化煤焦-CO2气化反应特性

基于拜耳法赤泥的综合利用和煤焦-CO2气化反应，提出利用拜耳法赤泥催化煤焦-CO2气化反应，在固定床热重分析仪上进行了拜耳法赤泥催化煤焦-CO2反应的研究。考察了拜耳法赤泥的添加方式、添加量及反应温度对煤焦-CO2的催化气化反应特性；并将拜耳法赤泥与K2CO3催化活性进行了对比；分析了拜耳法赤泥催化反应机理，采用了缩核模型、混合模型及修正的体积模型对拜耳法赤泥催化煤焦-CO2反应动力学进行了分析，结果表明：湿法添加拜耳法赤泥对煤焦-CO2具有很好的催化活性，而干法混合会抑制煤焦-CO2反应，因此选择湿法添加赤泥；得出拜耳法赤泥的最佳添加量为8%；随着温度的升高，煤焦-CO2催化气化反应性指数不断增加；在1 373.15 K时，8%拜耳法赤泥催化活性与该温度下10%含量的K2CO3催化性能相当；修正体积模型相比缩核模型、混合模型能够更好的解释催化气化动力学过程。因此，拜耳法赤泥对煤焦-CO2反应具有很好的催化作用，并且拜耳法赤泥还可以得到有效的利用。

Coal char-CO2 gasification reaction catalyzed by Bayer red mud

The coal char-CO2 gasification catalyzed by Bayer red mud was proposed,the catalytic coal char-CO2 gasification was carried out using a fixed-bed thermal-gravimetric analyzer.Effects of adding mode,adding content and reaction temperature of Bayer red mud on the gasification were studied.Catalytic gasification performance of Bayer red mud with K2CO3 was compared.Catalytic mechanism of Bayer red mud was analyzed.Kinetics of Catalytic coal char-CO2 gasification reaction were calculated by shrinking core model,mixing model and modified volumetric model.The main results are as following:Bayer red mud added by wet process shows a better catalytic performance compared with dry adding mode；the optimum adding amount is 8% by wet process；gasification reaction index increases with the increase of temperature；Performance of catalytic coal char-CO2 gasification using 8% amount of Bayer red mud is comparable with the 10% amount of K2CO3 at 1 373.15 K.Catalytic gasification reaction kinetics can be better explained by modified volumetric model than shrinking core model and mixing model.As a result,Bayer red shows an efficient catalytic performance for the coal char-CO2 reaction and it can be utilized effectively.