Ni-La2O3/C催化剂上甲醇羰基化反应性能的研究

以ＸＰＳ，ＴＲＰ技术和羰基化活性测试等手段研究了镧组分对Ｎｉ／Ｃ催化剂的表面组成，还原性能及羰基化反应性能的影响。结果表明：镧组分以Ｌａ２Ｏ３形式存在，Ｌａ２Ｏ３组分能够削弱氧化镍与活性炭之间的相互作用，促进ＮｉＯ的还原；适量的Ｌａ２Ｏ３组分还能促进ＮｉＯ在载体表面的分散，从而提高镍催化剂的羰基化活性，最佳Ｌａ含量为３．２％。浸渍次序对催化性能有一定的影响。其活性顺序为先浸镍后浸镧≈共浸〉先浸镧后

EFFECT OF La2O3 ON NI/C CATALYSTS FOR VAPOR PHASE CARBONYLATION OF METHANOL

La_2O_3-promoted Ni/C catalysts for methanol carbonylation were prepared by different impregnation methods.The structure, reduction behavior and catalytic performance of the catalysts were studied by TPR, XPS and carbonylation reaction.The results indicated that La_2O_3 could improve the Nickel dispersion and the reducibility.The promoting effect of La could be attributed to the synergistic effect between Ni and La which could cause a higher H_2 consumption with increasing La content and lower reduction temperature of Ni sites.The optimum content of La was 3.2 w%.Furthermore, The sequence of metal loading in preparing Ni-La_2O_3/C catalyst was observed to have an effect on the catalytic properties of the catalyst.Loading Ni before La results in a higher activity among the three methods.