LaNixCu1-xO3-λ钙钛矿在乙醇水蒸气重整制氢的实验研究

Experimental study on hydrogen production by steam reforming of ethanol with LaNixCu1-xO3-λperovskite

采用共沉淀法制备了掺杂不同Cu含量的钙钛矿LaNi x Cu 1-x O 3-λ(x=0.5,0.9,1.0)催化剂,并在450—700℃下于固定床反应器上进行蒸汽重整制氢实验。采用XRD研究了催化剂在反应前后的化学和结构性质,使用XRD,TPR,TGA-DTG等手段对合成的催化剂的结构和性能进行了表征和测试。结果表明:用一定量的铜对催化剂进行改性后,催化活性有所提高,且随着铜含量的增加,催化剂的催化活性进一步降低,其中LaNi 0.9 Cu 0.1 O 3-λ的性能最好,在700℃下乙醇转化率达到96.0%,氢气选择性为71.3%,与传统的钙钛矿催化剂相比,具有很高的抗结焦性,在700℃下48 h内没有出现失活现象。研究表明:Ni和Cu对Ni-Cu双金属微粒有增强作用,有助于提高LaNi x Cu 1-x O 3-λ钙钛矿型催化剂在ESR过程中的活性和稳定性,且铜修饰催化剂有较好的抗积炭性能。

The efficient LaNi x Cu 1-x O 3-λ(x=0.5,0.9,1.0)perovskite-type catalysts were synthesized by co-precipitation method and hydrogen production from ethanol steam reforming(ESR)was performed using the synthesized perovskite-type catalysts in a fixed-bed reactor at 450 to 700℃.XRD,TPR,TGA-DTG technologies were used to characterize and test the structures and properties of the synthesized catalysts.The results demonstrate that the catalytic activity of the perovskite-type catalysts for ESR can be improved after the modification with the certain amount of copper,and also decrease further with the copper content increasing.The LaNi 0.9 Cu 0.1 O 3-λpresented the best performance,the conversion of ethanol reached 96.0%at 700℃and the selectivity of hydrogen was 71.3%,and had high coking resistance compared to traditional perovskite catalysts and superior stability with no loss of activity during 48 h at 700℃.The studies indicate the enhanced effects between Ni and Cu on the small Ni-Cu bimetallic particles,which could contribute to the activity and stability of LaNi x Cu 1-x O 3-λperovskite-type catalysts in ESR process,and the copper modified catalyst had good anti coking performance.