HYDROTHERMAL GASIFICATION OF PHENOL WATER WITH NOVEL CARBON-METAL OXIDE COMPOSITE SUPPORTED Ru-MODIFIED Ni CATALYSTS

摘要

Catalysts deactivate at high temperatures in the steamnreforming reaction of aromatic compounds. Hydrothermalngasification reaction of wastewater containing water-solublenaromatic compounds can produce fuel gas in subcritical waterncondition. Highly active Ru/Al2O3 or Ni/AC catalysts have beennused in this process, but there were problems such as high costnwith noble metal and low loading amount of metal with smallnpore size of carbon supports.1,2) In this study, we have attemptednthe preparation of the catalyst for reforming aromatic compoundsnby hydrothermal gasification reaction in the subcritical waterncondition. We have already reported that the highly active andnsteady carbon-alumina composite supported Ni catalyst fornhydrothermal gasification of phenol water.1) However thisncatalyst showed rather low activity under the high concentrationnof phenol water. Therefore, we prepared carbon - metal oxidencomposite supported Ru-modified Ni catalysts, which would benmore active and steady for reforming of aromatic compounds, andncarried out hydrothermal gasification of phenol water as anwastewater model. The frame structure of phenol can be found innthe unit structure of not only coal but also biomass. Weninvestigated the effects of Ru promotion and kinds of supports onnthe activity and stability of hydrothermal gasification by changingnthe type of metal alkoxide precursor.