NOVEL APPROACH FOR CONTROLLING CATALYTIC SITE FOR LOW-TEMPERATURE STEAM REFORMING

为了获得高比表面积的低温水蒸气重整催化剂载体，采用异丙醇盐在苯中水解的方法制备了ZrO_2和ZrO_2-Y_2O_3。水解在80 ℃下使用过量的蒸馏水在流动的干燥氮气中进行。将由此获得的沉淀物在100 ℃下干燥，然后在500 ℃下在空气或氮气中煅烧1小时。ZrO_2和ZrO_2-Y_2O_3的比表面积均随水解加水量的增加而增加，ZrO_2-Y_2O_3的比表面积随Y含量的增加而增加。制备了比表面积为130 m^2/g的ZrO_2和比表面积为200 m^2/g的含15 mol% Y^<3+>的稳定化四元ZrO_2。此外，尽管ZrO_2和ZrO_2-Y_2O_3的晶体结构存在差异，但ZrO_2的晶格应变与表面积明确相关。

In order to obtain a high surface area support for the low-temperature steam reforming, ZrO_2 and ZrO_2-Y_2O_3 were prepared by the hydrolytic decomposition of the corresponding isopropoxide dissolved in benzene. The hydrolysis was carried out at 80ﾟC using an excess amount of distillled water in flowing dry nitrogen. The precipotates thus obtained were dried at 100ﾟC followed by calcination at 500ﾟC in air or nitrogen for 1 h. The specific surface areas for both of the ZrO_2 and ZrO_2-Y_2O_3 increased with increasing amount of water added for hydrolysis, and the surface areas for ZrO_2-Y_2O_3 increased with increasing yttrium content. A ZrO_2 having a surface area of 130m^2/g was produced, and a stabilized tetragonal ZrO_2 with 15 mol% Y^<3+> having a surface area of 200m^2/g was produced. Furthermore, despite the difference in the ZrO_2 and ZrO_2-Y_2O_3 crystal structures, the lattice-strain of ZrO_2 has been unequivocally related to the surface area.