We report herein on a new method to achieve a high yield of hydrocarbons from hydrothermal catalytic hydrodenitrogenation (HDN) of indole, which is higher than that from conventional pyrolysis methods. The main hydrocarbon products were aromatic hydrocarbons and alkanes, which are similar to fossil oils to be used as liquid fuels in the future. Catalyst screening experiments show that noble metal catalysts (e.g., 5 wt % Pt, Pd, or Ru) supported on porous solids (e.g., carbon, Al₂O₃) enhanced the conversion of indole to hydrocarbons under hydrothermal condition. Of those different catalysts, Pd/γ-Al₂O₃ shows the greatest influence on the yield of hydrocarbons, which we focus on the catalyst Pd/γ-Al₂O₃ in more details. On the basis of the Pd/γ-Al₂O₃ catalyst, the effects of time, temperature, and H₂ pressure on the hydrocarbons were discussed. HDN of the indole reaction at 450 °C, 0.015 g/cm³ water density, 5 MPa H₂, and 50 wt % Pd/γ-Al₂O₃ loading led to a maximum yield (51 mol %) of hydrocarbons at 120 min. It proposes the mechanism to acquire hydrocarbons from hydrogenational indole denitrogenation, which experiences two different pathways, as (1) indole is directly hydrodenitrogenated into hydrocarbons, and (2) intermediate oxygenated products from hydrolysis of partly hydrodenitrogenated indole were hydrodeoxygenated to removal of O to acquire hydrocarbons. The factors for deactivation of catalyst under hydrothermal condition are also discussed by the results from characterizing the surface, bulk structure, and microscopy experiments.

中文翻译：

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水热条件下吲哚催化加氢脱氮制得的烃产量高

我们在此报告了一种新方法，该方法可从吲哚的水热催化加氢脱氮（HDN）中获得较高的烃收率，该收率要高于常规热解方法。主要的碳氢化合物产品是芳香烃和烷烃，与将来用作液体燃料的化石油相似。催化剂筛选实验表明，负载在多孔固体（例如碳，Al ₂ O ₃）上的贵金属催化剂（例如5wt％的Pt，Pd或Ru ）可提高在水热条件下吲哚向烃类的转化率。这些不同的催化剂，钯/γ-Al系₂ ö ₃示出了对烃的收率的影响最大，这是我们着眼于催化剂的Pd /γ-Al系₂ ö₃更详细。上的Pd /γ-Al的基础₂ Ó ₃催化剂，时间，温度，和H的影响₂进行了讨论的烃压力。在450℃的吲哚反应的HDN 0.015克/厘米³水的密度，为5MPaħ ₂，和50重量％的Pd /γ-Al系₂ ö ₃负载导致在120分钟时碳氢化合物的最大收率（51 mol％）。提出了通过氢化吲哚脱氮获得烃的机理，该机理经历了两种不同的途径，（1）吲哚被直接加氢脱氢成烃，（2）部分加氢脱氮的吲哚水解产生的中间氧化产物被加氢脱氧以除去O，从而获得O。碳氢化合物。通过表征表面，本体结构和显微镜实验的结果，还讨论了在水热条件下催化剂失活的因素。