褐炭液化溶剤成分の二次水素化処理 (II)
1988 年 67 巻 1 号 p. 28-34
詳細
1988 年 67 巻 1 号 p. 28-34
A coal derived middle distillate produced from the liquefaction of Australian brown coal using a bench unit, was subjected to hydrotreatment on NiMo/Al2O3 and NiW/Al2O3 in a fixed bed reactor of 20 ml in volume at 350-390°Cunder hydrogen pressure of 100 kg/cm2 G with LHSV of 1 h-1. Further, catalytic hydrogenation of model mixture was carried out at 370°C on NiMo/Al2O3 with the same equipment to clarify the influence of phenols and quinolines, which occupied the significant amount of the feed oil, on the hydrogenation reactivi-ty.
Most of phenols were reduced to hydrocarbons at 390°C over NiMo/Al2O3, but at lower reaction temperatures, ortho-substituted alkylphenols gave lower conversions than those of meta-and para-isomers. Sterically hindered 2, 6-dimethylphenol also showed the poorest conver-sion (21‰) at 370°C compared to ortho-dimethylphenols;
3, 4-(96‰) >2, 3-(87‰) >2, 4-(76‰) >2, 5-(58‰) >2, 6-dimethylphenol.
Basic constituents in the crude oil were reduced almost completely at 390°C over NiMo/ Al2O3 except carbazole (HDN 98.6‰).
Hydrotreatment of the mixture comparising of p-cresol, quinoline, biphenyl and 1-methylnaphthalene showed that the increasing p-cresol content (0-14.2 mol‰) gave no noticiable effect on the hydrogenation degree of each component. On the other hand, addition of quinoline (0-6.2 mol‰) causes a considerable decrease of methyldecalin yield and biphenyl con-version, indicating the deactivation of catalyst by the adsorption of bases. Nitrogen content rather than that of phenolics in the recycle solvent should be one of the critical factors to affect the catalytic hydrogenation reactivity at the upgrading stage.
