甲烷与二氧化碳重整制取合成气反应的研究 (I)Sr_(1-x)La_xNiAl_(11)O_(19)催化活性表征

对具有磁铅石结构的Ｓｒ１－ｘＬａｘＮｉＡｌ１１Ｏ１９对甲烷与二氧化碳重整反应的催化活性、积炭量和稳定性进行了研究．不同还原温度下催化剂的ＸＲＤ和催化活性的实验结果表明，金属镍是ＣＨ４＋ＣＯ２重整反应的活性组分，金属镍含量越大，反应活性越高．反应后催化剂积炭量的分析结果说明，在相同镍含量和分散度的情况下，Ｌａ３＋离子对Ｓｒ２＋离子调变，可以降低催化剂的表面酸性，提高催化剂的抗积炭能力．ＬａＮｉＡｌ１１Ｏ１９是一种具有较好催化活性、稳定性和抗积炭性能的催化剂．

Study of Methane Reforming with Carbon Dioxide to Synthesis Gas (II) Characterization of Catalytic Activity of Sr 1- x La x NiAl 11 O 19

In this paper, the catalytic activity, coking amount and stability of Sr 1- x La x NiAl 11 O 19 for methane reforming with carbon dioxide were inverstigated. It was found that the metallic nickel was active species for this reaction, the conversions of CH 4 and CO 2 increase with increasing amount of metallic nickel in catalysts. While there is a similar content of nickel in catalysts, the partial substitution of Sr 2+ by La 3+ shows unremarkable effect on the catalytic activity for reforming reaction due to the similar dispersion of Ni. Whereas, such substitution has great effect on the acidity of catalyst, and the number of acidic sites and amount of carbon deposition on the catalyst decrease with the increase of La 3+ content. So it is evident that carbon deposition in carbon dioxide reforming of methane can be suppressed by decreasing the acidity of the catalyst. In addition, LaNiAl 11 O 19 with a high catalytic activity, good stability and excellent resistance to carbon deposition is the best in the series of Sr 1- x La x NiAl 11 O 19 catalysts.