基于脱氧提质的微波加热生物质化学链热解及介-微孔复合分子筛催化重整制油机理研究

The primary bio-oil derived from catalytic fast pyrolysis dominates some deficiencies such as the high oxygen content in the liquid products, low efficiency of catalytic reform as well as the high consumption of energy, which largely inhibited the development of biomass utilization. Therefore, it is urgent to make some efforts to solve those key problems so as to obtain an upgraded bio-fuel production. In this project, we will conduct a series of fundamental research on deoxygenation of bio-fuel and promotion of catalytic reforming (CR) efficiency via a microwave assisted catalytic fast pyrolysis in a fluidized bed system. Firstly, the deoxygenation mechanism for chemical looping pyrolysis (CLP) of biomass will be studied, and the modification methods for improving the deoxygenation ability will be explored. In addition, the influence of chemical reaction and reduction properties on oxygen carrier reduction process also will be discussed. Secondly, the effect of porosity inside the compound zeolite with a hierarchical micro-mesoporous system on the catalytic performance will be investigated thoroughly. Simultaneously, the three dimensional hierarchical micro-mesoporous zeolites will be designed and developed so as to advance the catalytic performance. Last but not least, the coupling mechanism of deoxygenation reaction in CLP and hierarchical micro-mesoporous system in CR will be analyzed, and the numerical modeling by DEM-CFD with respect to study the multiple phase flowing mechanics, heat and mass transfer, as well as the chemical reaction mechanism. The velocity profile, temperature field and products distribution inside the microwave assisted fluidized bed will be studied in terms of forecast the yields of liquid products, hydrocarbons, gases and bio-char. Therefore, the fundamental research conducted in this project will be beneficial for the development of novel technique in high quality bio-fuel production, and thus reliefs the petroleum shortage in China.

针对目前生物质催化热解制油领域存在初级热解油含氧量较高、催化重整脱氧效果不佳、热解过程热利用效率不高等一系列关键问题，本项目将开展基于脱氧提质的微波加热生物质化学链热解及介-微孔复合分子筛催化重整制油机理研究，探究生物质化学链热解脱氧的机理，探索增强脱氧性能的改性措施，阐明载氧体还原过程的化学过程、去氧再生还原特性等影响机制；深入研究介孔-微孔复合分子筛的孔道特性对催化机制的影响，并设计研发三维有序介孔-微孔“核-壳”复合体系催化剂，提高催化剂的性能；探索在微波加热条件下化学链热解脱氧与介孔-微孔复合分子筛催化重整的耦合机制，并对该过程的多相流动力学、传热传质规律与化学反应机理进行离散单元方法-计算流体力学（DEM-CFD）数值模拟，研究微波加热流化床中速度场、温度场、产物浓度分布，预测气、液、固产率及生物油中烃类的含量。本项目将形成新型生物质制油方法，对于缓解我国石油短缺，具有重要意义。

针对目前生物质催化热解制油领域存在初级热解油含氧量较高、催化重整脱氧效果不佳、热解过程热利用效率不高等一系列关键问题，开展了基于脱氧提质的微波加热生物质化学链热解及介-微孔复合分子筛催化重整制油机理研究，探究了生物质化学链热解脱氧的机理，探索了增强脱氧性能的改性措施，阐明了载氧体还原过程的化学过程、去氧再生还原特性等影响机制；探索了在微波加热条件下化学链热解脱氧与介孔-微孔复合分子筛催化重整的耦合机制，并对该过程的多相流动力学、传热传质规律与化学反应机理进行了离散单元方法-计算流体力学（DEM-CFD）数值模拟，研究了微波加热流化床中速度场、温度场、产物浓度分布。以制备的介微孔复合分子筛催化剂为催化重整媒介，比较了流化床与固定床的热解稻壳的区别，使用微波流化床的液相产率明显上升，生物油产物中碳氢化合物的相对含量明显高于固定床热解产物中的相对含量。催化剂的增加会促进脱羰和脱羧反应，从而产生更多的烃类化合物，但是过多的催化剂的添加并不能导致更高的单环芳烃选择性。随着再生次数的增加，介微孔复合分子筛催化剂的重复使用性高，不易结焦。对未来的大规模生产使用，提供了可能性。数值模拟结果表明，较大的流化速度使颗粒能更快地达到良好混合的状态；直径较小的生物质颗粒对应着较好的混合质量。