甲烷部分氧化铑基催化剂的活性中心本质研究

采用脉冲反应技术,研究了ＣＨ４、ＣＨ４／Ｏ２（２／１）在还原态和氧化态铑基催化剂上的反应情况。观察到,在第一个ＣＨ４／Ｏ２（２／１）脉冲反应点中,氧化态催化剂上的甲烷转化率、ＣＯ２选择性显著高于还原态催化剂;从第二个脉冲反应点开始,氧化态催化剂上的甲烷转化率、产物选择性均与还原态催化剂上的基本接近,表明在第一个ＣＨ４／Ｏ２（２／１）脉冲反应点中,氧化态催化剂中的铑氧化物已被甲烷还原至金属态铑;从第二个脉冲反应点开始,ＣＨ４＋Ｏ２反应实际上在还原态的铑位上进行。由此推断,金属态铑是甲烷部分氧化制合成气的活性位

Studies on preparation of catalyst for light olefin synthesis via carbon monoxide hydrogenation

The method of "multiple step reflux impregnation" is put forward in this article for preparing high dispersion and high iron content supported catalyst for light olefin synthesis via carbon monoxide hydrogenation, with Fe 3(CO) 12 being the precursor.Characterization by XRD and other techniques shows that,although the iron content is high at 11%(mass), the state of iron on the surface of the catalyst support is in high dispersion.Effects of different temperatures of decarbonylation, iron contents and supports on catalyst preparing chemistry are also investigated.It is found that an iron content of 5.4 %(mass),using Y zeolite as a support and decarbonylating at 300℃ are more favourable and ZSM 5 is a best support.The catalyst using ZSM 5 as support exhibits an excellent selectivity of 99.8% to light olefin.