CONTINUOUS PRODUCTION OF HYDROGEN FROM METHANE WITHOUT CARBON DIOXIDE PRODUCTION

研究了甲烷分解制氢而不产生二氧化碳的生产技术。利用固定床反应器进行了催化剂的研制工作。在本研究中，为了连续生产氢和碳，对流化床系统进行了研究。制备了载体负载镍催化剂。反应温度为500 ~ 550℃。流化床用柱的内径为12 mm。由于尺寸太小，无法建立工业上使用的流化状态。然而，催化剂颗粒是在反应器中移动的。颗粒直径约为60 × 10-6 m。采用二氧化硅、氧化铝和活性炭作为催化剂载体。二氧化硅负载催化剂的反应速率最高。随着Ni负载的增加，单位重量Ni的碳沉积量增加。在固定床的情况下，反应器在120 h后被沉积在催化剂上的碳堵塞。然而，在流化床反应器中没有观察到堵塞。这是流化床利用的优点之一。为了保证反应器的良好流化质量，对沉积碳的催化剂颗粒的流动性进行了研究。破碎二氧化硅支架的流动性在30 min后下降。静息角随反应时间和积碳量的增加而增大。破碎二氧化硅支架的初始休止角值较大。另一方面，在9 h的反应过程中，球形氧化铝载体的值很小，并且观察到良好的流动性。

The production technique in which hydrogen is produced from the methane decomposition without the production of carbon dioxide was studied. Some works using fixed bed reactor have been carried out to develop catalysts. In this study, in order to produce hydrogen and carbon continuously, the fluidized bed system was studied.Nickel catalyst supported on carriers were prepared. The reaction temperature was 500-550℃. The inner diameter of column used for a fluidized bed was 12 mm. Since the size was too small to establish the fluidizing state utilized industrially. However, the catalyst particle were moved in the reactor. The particle diameter was about 60 x 10-6 m.Silica, alumina and active charcoal were used as a catalyst supports. The highest reaction rate was obtained for silica supported catalyst. The deposition of carbon per unit weight of Ni increased with Ni loading. In the case of a fixed bed, the reactor was blocked by the deposited carbon on the catalyst after 120 h. However, the plugging was not observed for a fluidized bed reactor. This is one of the advantages of the fluidized bed utilization.Since to keep a good fluidization quality to operate as a reactor, the fluidity of the catalyst particles on which carbon deposited was investigated. The fluidity of crashed silica support decreased after 30 min. The angle of repose increase with reaction time and carbon deposition. The initial value of the angle of repose for the crashed silica support was high. On the other hand, the value of the spherical alumina support was small and the good fluidity was observed during 9 h reaction.