Department of Aeronautics and Astronautics, National Cheng Kung University, Tainan, 701, Taiwan, ROC; Research Center for Smart Sustainable Circular Economy, Tunghai University, Taichung 407, Taiwan; Department of Mechanical Engineering, National Chin-Yi University of Technology, Taichung, 411, Taiwan, ROC.
Department of Aeronautics and Astronautics, National Cheng Kung University, Tainan, 701, Taiwan, ROC.
Chemosphere. 2021 May;271:129510. doi: 10.1016/j.chemosphere.2020.129510. Epub 2020 Dec 31.
Zeolite socony mobil-5 (ZSM-5) is a common catalyst used for biomass pyrolysis. Nevertheless, the quantitative information on the catalytic behavior of ZSM-5 on biomass pyrolysis is absent so far. This study focuses on the catalytic pyrolysis phenomena and mechanisms of biomass wastes using ZSM-5 via thermogravimetric analyzer and pyrolysis-gas chromatography/mass spectrometry, with particular emphasis on catalytic level identification and aromatic hydrocarbons (AHs) formation. Two biomass wastes of sawdust and sorghum distillery residue (SDR) are investigated, while four biomass-to-catalyst ratios are considered. The analysis suggests that biomass waste pyrolysis processes can be divided into three zones, proceeding from a heat-transfer dominant zone (zone 1) to catalysis dominant zones (zones 2 and 3). The indicators of the intensity of difference (IOD), catalytic effective area, catalytic index (CI), and aromatic enhancement index are conducted to measure the catalytic effect of ZSM-5 on biomass waste pyrolysis and AHs formation. The maximum IOD occurs in zone 2, showing the highest intensity of the catalytic effect. The CI values of the two biomass wastes increase with increasing the biomass-to-catalyst ratio. However, there exists a threshold for sawdust pyrolysis, indicating a limit for the catalytic effect on sawdust. The higher the catalyst addition, the higher the AHs proportion in the vapor stream. When the biomass-to-catalyst ratio is 1/10, AHs formation is intensified significantly, especially for sawdust. Overall, the indexes conducted in the present study can provide useful measures to identify the catalytic pyrolysis dynamics and levels.
沸石 socony mobil-5（ZSM-5）是一种常用的生物质热解催化剂。然而，目前还缺乏关于 ZSM-5 对生物质热解催化行为的定量信息。本研究通过热重分析仪和热解气相色谱/质谱联用仪，重点研究了 ZSM-5 对生物质废弃物的催化热解现象和机制，特别关注了催化水平的识别和芳烃（AHs）的形成。研究了两种生物质废弃物——木屑和高粱酿酒厂残渣（SDR），同时考虑了四种生物质与催化剂的比例。分析表明，生物质废弃物热解过程可分为三个区域，从热传递主导区域（区域 1）到催化主导区域（区域 2 和 3）。采用强度差异指标（IOD）、催化有效面积、催化指数（CI）和芳烃增强指数来衡量 ZSM-5 对生物质废弃物热解和 AHs 形成的催化效果。IOD 的最大值出现在区域 2，表明催化效果最强。两种生物质废弃物的 CI 值随生物质与催化剂比例的增加而增加。然而，木屑热解存在一个阈值，表明对木屑的催化效果有限。催化剂添加量越高，气相中 AHs 的比例越高。当生物质与催化剂的比例为 1/10 时，AHs 的形成显著增强，特别是对木屑而言。总的来说，本研究中采用的指标可以为识别催化热解动力学和水平提供有用的措施。
