| Coal pyrolysis liquids are rich in olefinic, phenolic and aromatic compounds, but traditional hydroprocessing destroys their inherent synthetic values. Acid catalyzed processes are not considered, because coal pyrolysis liquids also contain nitrogen bases. We aim to find appropriate catalysts that can conduct acid catalysis in the presence of nitrogen bases.;Catalytic aromatic alkylation using phenol and 1-hexene without and with pyridine was selected as model reaction at 315°C. Different alumina and silica-alumina (1-40 wt% silica) catalysts were characterized. Siral30, the catalyst with the highest medium strength acidity, performed best when the feed contained a nitrogen base. Siral40, the catalyst with the highest strong Bronsted acidity, performed best in the absence of nitrogen bases. Hydration affected the catalysis and had to be controlled. Autocatalysis of phenol alkylation with alkenes can also proceed and was responsible for a minor contribution to the overall conversion. The reaction products were mainly ortho-C-alkylphenols. |
