Abstract:

The catalytic steam reforming of phenol for hydrogen production was realized under mild conditions (523－723 K) over a Raney Ni catalyst.The conversion of phenol and selectivity of H₂ were highly dependent upon the reaction conditions, such as temperature, liquid hourly space velocity (LHSV), and phenol concentrations.A higher temperature and lower LHSV could increase the conversions of phenol, but decrease the selectivity of H₂.When compared with the aqueous-phase reforming of phenol for hydrogen, however, a higher reaction temperature and the vaporization of the liquid solution are generally required for the steam reforming process, but it shows a significantly higher H₂ selectivity (93%－100%) than the aqueous-phase reforming.Additionally, the steam reforming of phenol over the Raney Ni catalyst was carried out under milder conditions than those reported in literatures, meanwhile, the Raney Ni catalyst was quite stable (60 h) for the phenol steam reforming process, and the content of CO in the gas effluent was quite low (molar ratio of CO/CO₂ was 0.01—0.2).Therefore, H₂ produced can be used as hydrogen source directly.

Key words:

苯酚, 水蒸气重整, H₂, Raney Ni催化剂

摘要：

以Raney Ni为催化剂，在温和条件下(523～723 K)实现了苯酚催化水蒸气重整制氢反应。研究表明，反应温度、液体空速和原料浓度等反应条件是影响苯酚转化率和H₂选择性的重要因素，较高的反应温度和较低的液体空速有利于提高苯酚转化率，但不利于提高H₂选择性。对比苯酚水相重整制氢过程发现，尽管水蒸气重整反应温度相对较高，且需要汽化原料使反应在气相中进行，但该过程具有比水相重整更高的H₂选择性(93%～100%)。此外，Raney Ni催化剂上苯酚水蒸气重整反应与现有的文献结果比较还具有反应条件温和、催化剂稳定性好(60h)以及CO含量低(CO/CO₂摩尔比为0.01～0.2)等优点。将该技术应用于工业含酚有机废水的资源化处理制备的H₂可以直接作为氢源使用。

关键词:

苯酚, 水蒸气重整, H₂, Raney Ni催化剂