Bayazed Mohammed, Fakeeha Anis H, Ibrahim Ahmed A, Alanazi Yousef M, Abasaeed Ahmed E, Khan Wasim U, Abu-Dahrieh Jehad K, Al-Fatesh Ahmed S
Chemical Engineering Department, College of Engineering, King Saud University, P.O. Box 800, Riyadh, 11421, Saudi Arabia.
IRC Refining and Advanced Chemicals, Research Institute, King Fahd University of Petroleum and Minerals, Dhahran, 31261, Saudi Arabia.
ChemistryOpen. 2023 Sep;12(9):e202300112. doi: 10.1002/open.202300112.
Methane decomposition is a promising route to synthesize CO -free hydrogen and carbon nanomaterials (CNM ). In this work, the impregnation method was employed for the preparation of the catalysts. Systematic investigations on the activity and stability of Fe-based catalysts were carried out in a packed-bed micro-activity reactor at 800 °C with a feed gas flow rate of 18 mL/min. The effect of doping Y O , MgO, SiO and TiO over ZrO on the catalytic performance was also studied. BET revealed that the specific surface areas and pore volumes are increased after SiO , TiO , and Y O are added to ZrO while MgO had a negative impact and hence a little decrease in specific surface area is observed. The catalytic activity results showed that the Fe-based catalyst supported over TiO -doped ZrO that is, Fe-TiZr, demonstrated the highest activity and stability, with a maximum methane conversion of 81.3 % during 180 min time-on-stream. At 800 °C, a maximum initial methane conversion of 73 %, 38 %, 64 %, and 69 % and a final carbon yield of 121 wt. %, 55 wt. %, 354 wt. %, and 174 wt. % was achieved using Fe-MgZr, Fe-SiZr, Fe-TiZr and Fe-YZr catalysts, respectively. Moreover, bulk deposition of uniform carbon nanotubes with a high degree of graphitization and different diameters was observed over the catalysts.
甲烷分解是一种很有前景的合成无CO氢气和碳纳米材料（CNM）的途径。在这项工作中，采用浸渍法制备催化剂。在填充床微活性反应器中于800 °C、进料气体流速为18 mL/min的条件下，对铁基催化剂的活性和稳定性进行了系统研究。还研究了在ZrO上掺杂Y₂O₃、MgO、SiO₂和TiO₂对催化性能的影响。BET结果表明，向ZrO中添加SiO₂、TiO₂和Y₂O₃后，比表面积和孔体积增加，而MgO有负面影响，因此比表面积略有下降。催化活性结果表明，负载在TiO₂掺杂ZrO上的铁基催化剂，即Fe-TiZr，表现出最高的活性和稳定性，在180 min的反应时间内甲烷转化率最高可达81.3 %。在800 °C下，使用Fe-MgZr、Fe-SiZr、Fe-TiZr和Fe-YZr催化剂分别实现了73 %、38 %、64 %和69 %的最大初始甲烷转化率以及121 wt.%、55 wt.%、354 wt.%和174 wt.%的最终碳产率。此外，在催化剂上观察到了大量具有高度石墨化和不同直径的均匀碳纳米管沉积。
