Steam Reforming of Ethanol over Ni/Al2O3鈭扡a2O3 Catalysts Synthesized by Sol鈭扜el

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• 作者：Rau虂l Carrera Cerritos ; Rosalba Fuentes Rami虂rez ; Alberto F. Aguilera Alvarado ; J. Merced Marti虂nez Rosales ; Toma虂s Viveros Garci虂a ; Ignacio R. Galindo Esquivel
• 刊名：Industrial & Engineering Chemistry Research
• 出版年：2011
• 出版时间：March 2, 2011
• 年：2011
• 卷：50
• 期：5
• 页码：2576-2584
• 全文大小：940K
• 年卷期：v.50,no.5(March 2, 2011)
• ISSN：1520-5045

文摘

The activity of Ni/Al₂O₃鈭扡a₂O₃ catalysts prepared by sol鈭抔el process for hydrogen production using ethanol steam reforming was studied. The effect of Ni and La loading in the reaction activity and hydrogen selectivity was analyzed. The catalytic measurements were performed on a fixed-bed microreactor for a 6 h period; within this time, the catalysts showed partial deactivation. The catalyst containing 12 wt % La showed the highest yield to H₂, but it also presented the highest deactivation. The other catalysts with the same Ni loading showed a decrease in H₂ yield over time. The increase of Ni loading from 5 to 10 wt % caused an increase in H₂ and CO yields in all La containing catalysts. The catalyst supported on sol鈭抔el synthesized alumina showed the highest activity after 6 h on stream. This catalyst showed the lowest deactivation from all the systems that were studied. Polymeric and graphitic carbon were identified by DTA analysis of the spent catalysts. TGA analysis showed that the total coke deposited after reaction followed the trend: Ni/Al > Ni/12La 鈮?Ni/8La > Ni/5La. However, less graphitic coke was identified on the catalysts as the lantana loading increased in the supports. Additionally, TEM results indicate that the radius of the graphite tubes decreased as the concentration of La in the support increased. A slight increase of H₂ and CO₂ yields was obtained when the water to ethanol mole ratio increased from 3 to 6. Higher deactivation was observed when more steam was fed to the reaction, even when lower carbon contents were determined by DTA-TGA analysis.