论文部分内容阅读
通过对催化剂载体孔隙结构的系统研究,由商品微球型硅胶经扩孔处理,成功地制得了甲醇氧化制甲醛的沸腾床铁-钼氧化物催化剂。结果表明,载体以及催化剂的孔隙结构对催化剂活性和选择性均有显著影响,是决定催化剂性能的重要因素。在本催化过程中,催化剂表面以小于30米~2/克、孔半径以大于200为宜。热差以及X-衍射分析表明,催化剂的活性组分系由Fe_2(MoO_4)_3+MoO_3所组成。通过对催化剂顺磁共振谱的分析,认为铁-钼氧化物催化剂的氧化中心,应和表面可还原的Fe~(+3)及Mo~(+6)离子有关。并以此为根据,按“氧化还原”机理,对甲醇氧化的机理做了理论上的阐述。
Through the systematic study of the pore structure of the catalyst carrier, the ebullated bed iron-molybdenum oxide catalyst for the methanol oxidation to formaldehyde was successfully obtained from the commercial microsphere-type silica gel by reaming. The results show that the pore structure of the support and the catalyst have a significant effect on the catalyst activity and selectivity, which is an important factor in determining the catalyst performance. In this catalytic process, the catalyst surface is less than 30 m ~ 2 / g, a pore radius greater than 200 is appropriate. Thermal diffusivity and X-ray diffraction analysis show that the active component of the catalyst consists of Fe 2 (MoO 4) 3 + MoO 3. By analyzing the paramagnetic resonance spectrum of the catalyst, it is considered that the oxidation center of the iron-molybdenum oxide catalyst should be related to the surface reducible Fe ~ (+3) and Mo ~ (+6) ions. And based on this, according to “redox” mechanism, the mechanism of methanol oxidation is theoretically elaborated.