Ni-La催化剂上乙醇水蒸气重整制氢——燃料电池氢源技术

Hydrogen production for fuel cell via ethanol steam reforming reaction over Ni-La catalysts

采用浸渍法制备出γ-Al2O3、SiO2和γ-Al2O3.SiO2负载的Ni-La催化剂,用XRD、TPR、XPS、H2-TPD、NH3-TPD和TG等手段对催化剂进行了表征,结果表明:这3种负载型催化剂中的活性组分Ni的分散度较高,La3+氧化物高度分散于载体表面.在温度为400℃、水醇比为4.0和液体空速为8.0 mL h-1gc-at1的条件下,催化剂进行稳定性测试,结果表明:γ-Al2O3.SiO2负载的Ni-La催化剂在整个100 h稳定性测试过程中,氢气的选择性保持在67.0%左右,且稳定性良好.对经过稳定性测试后的Ni-La催化剂进行热重分析,发现γ-Al2O3.SiO2负载的Ni-La催化剂具有较少的积碳量,仅仅是0.86 g C.gc-at1,其中石墨碳占42.81%.

Ni-La catalysts supported on γ-Al2O3 , SiO2and γ-Al2O3 · SiO2 were prepared using impregnation methods. The structure and surface characteristics of the catalysts were measured by XRD, TPR, XPS, H2-TPD, NH3- TPD and TG. It revealed that these catalysts had higher Ni metal dispersion degree, and La^3＋ oxides were highly dispersed in the catalysts. The stability of the catalysts with different supports was examined at T = 400 ℃, LSHV = 8 mL g ^-1 h ^-1, water / ethanol ratio = 4.0, and found that the hydrogen selectivity remained about 67.0% during the whole 100 h over Ni-La catalyst supported on γ-Al2O3 · SiO2. TG results were used to detect the carbon deposited on the catalysts and found that the deposition carbon over Ni-La catalyst supported on γ-Al2O3 · SiO2 was only 0.86 gC gcat^-1, among which graphite carbon was about 42.81%.