School of Environmental Engineering, University of Seoul, Seoul, 02504, Republic of Korea.
Department of Environmental and Safety Engineering & Department of Energy Systems Research, Ajou University, Suwon, 16499, Republic of Korea.
Environ Pollut. 2021 Aug 15;283:117060. doi: 10.1016/j.envpol.2021.117060. Epub 2021 Apr 1.
In this study, wasted mask is chosen as a pyrolysis feedstock whose generation has incredibly increased these days due to COVID-19. We suggest a way to produce value-added chemicals (e.g., aromatic compounds) from the mask with high amounts through catalytic fast pyrolysis (CFP). To this end, the effects of zeolite catalyst properties on the upgradation efficiency of pyrolytic products produced from pyrolysis of wasted mask were investigated. The compositions and yields of pyrolytic gases and oils were characterized as functions of pyrolysis temperature and the type of zeolite catalyst (HBeta, HY, and HZSM-5), including the mesoporous catalyst of Al-MCM-41. The mask was pyrolyzed in a fixed bed reactor, and the pyrolysis gases evolved in the reactor was routed to a secondary reactor inside which the zeolite catalyst was loaded. It was chosen 550 °C as the CFP temperature to compare the catalyst performance for the production of benzene, toluene, ethylbenzene, and xylene (BTEX) because this temperature gave the highest oil yield (80.7 wt%) during the non-catalytic pyrolysis process. The large pore zeolite group of HBeta and HY led to 134% and 67% higher BTEX concentrations than HZSM-5, respectively, likely because they had larger pores, higher surface areas, and higher acid site density than the HZSM-5. This is the first report of the effect of zeolite characteristics on BTEX production via CFP.
在这项研究中，废弃口罩被选为热解原料，由于 COVID-19 的原因，其产量近年来大幅增加。我们提出了一种通过催化快速热解（CFP）从大量口罩中生产增值化学品（例如芳香族化合物）的方法。为此，研究了沸石催化剂特性对废弃口罩热解产物升级效率的影响。作为热解温度和沸石催化剂类型（HBeta、HY 和 HZSM-5）的函数，包括介孔催化剂 Al-MCM-41，对热解气体和油的组成和产率进行了表征。口罩在固定床反应器中热解，反应器中产生的热解气被引导到装有沸石催化剂的二级反应器中。选择 550°C 作为 CFP 温度，以比较生产苯、甲苯、乙苯和二甲苯（BTEX）的催化剂性能，因为在非催化热解过程中，该温度下油的产率最高（80.7wt%）。HBeta 和 HY 的大孔沸石组分别导致 BTEX 浓度比 HZSM-5 高 134%和 67%，这可能是因为它们的孔径、比表面积和酸位密度都高于 HZSM-5。这是关于沸石特性对 CFP 生产 BTEX 的影响的首次报道。
