改良的5A分子筛载Ni催化剂上甘油水蒸汽重整制合成气

Preparation of syngas via steam reforming of glycerol over modified Ni/LTA catalysts

以Linde型5A分子筛(LTA)为载体,采用浸渍法制备了金属氧化物修饰的负载型Ni基催化剂,并用于甘油水蒸汽重整制合成气。催化剂表征及催化稳定性的考察结果表明Mo、La、Ca氧化物的同时修饰可抑制Ni/LTA催化剂中活性组分Ni与载体LTA的相互作用,在甘油重整反应中具有较好的稳定性能。反应工艺考察结果表明,NiMoLaCa/LTA在反应温度600℃、原料液中甘油/水的体积比3∶7、LHSV为2.67h-1的条件下,甘油重整反应产物气有理想的n(H2)/n(CO)比2.06;升高反应温度、降低甘油/水体积比和减小LHSV均可提高甘油的产气率,但会加快CO的水气变换反应;CO和CO2的甲烷化反应受反应温度的影响较大。

Ni based catalysts supported on Linde type 5A molecular sieves （LTA） modified by metal oxides were prepared by impregnation, and used for catalyzing glycerol steam reforming （GSR） to syngas. The results of the characterization and catalytic stability tests of the catalysts showed that the co-modification with Mo, La and Ca oxides could weaken the stronger interaction between active species Ni and support LTA in Ni/LTA catalysts, which improved the catalytic stability of NiMoLaCa/LTA in GSR. The effects of reaction parameters on GSR reaction over NiMoLaCa/LTA were investigated, and the resuhs showed that under the conditions of temperature of 600℃, volume ratio of glycerol to water of 3：7 and LHSV of 2.67h-1, the produced gaseous product had a ideal H2/CO molar ratio of 2.06; a higher temperature, lower glycerol/water volume ratio and LHSV were helpful to improve GSR reaction and CO water-gas shift reaction; and the reactions of CO and CO2 methanation were obviously related to temperature.