Abstract: Improved supported hydroprocessing catalysts, and their method of preparation useful for the hydrodesulfurization (HDS) and hydrodenitrogenation (HDN) of a petroleum feedstock, including a residuum hydrocarbon feedstock are disclosed. The Catalysts contain at least one Groups VIB metal component, at least one Group VIII metal component, and a phosphorus component, supported on a foraminous support such as alumina. The supported catalysts are characterized by a specific combination of properties, namely, the Group VIII metal to Phosphorous molar ratio, the Group VIII metal to Group VIB metal molar ratio, the phosphorous component to Group VIB component molar ratio and the median pore diameter. The resulting catalysts exhibit enhanced HDN without sacrificing to any significant degree the HDS activity.

Abstract: Improved supported hydroprocessing catalysts, and their method of preparation useful for the hydrodesulfurization (HDS) and hydrodenitrogenation (HDN) of a petroleum feedstock, including a residuum hydrocarbon feedstock are disclosed. The Catalysts contain at least one Groups VIB metal component, at least one Group VIII metal component, and a phosphorus component, supported on a foraminous support such as alumina. The supported catalysts are characterized by a specific combination of properties, namely, the Group VIII metal to Phosphorous molar ratio, the Group VIII metal to Group VIB metal molar ratio, the phosphorous component to Group VIB component molar ratio and the median pore diameter. The resulting catalysts exhibit enhanced HDN without sacrificing to any significant degree the HDS activity.

Abstract: A method for producing a hydrorefining catalyst has the steps of preparing an impregnation solution containing molybdenum, phosphorus, cobalt and/or nickel, and citric acid, bringing a carrier into contact with the impregnation solution, and then calcinating the carrier in an oxidizing atmosphere at a temperature at which citric acid is removed. In the impregnation solution, a molar ratio of molybdenum/phosphorus is 6 to 13, a molar ratio of (cobalt and nickel)/phosphorus is 0.5 to 7, and a molar ratio of (cobalt and nickel)/citric acid is 0.5 to 2. As for the hydrorefining catalyst obtained by this method, the activity of the catalyst is high, and the catalyst life is long.

Abstract: A method for producing a hydrorefining catalyst has the steps of preparing an impregnation solution containing molybdenum, phosphorus, cobalt and/or nickel, and citric acid, bringing a carrier into contact with the impregnation solution, and then calcinating the carrier in an oxidizing atmosphere at a temperature at which citric acid is removed. In the impregnation solution, a molar ratio of molybdenum/phosphorus is 6 to 13, a molar ratio of (cobalt and nickel)/phosphorus is 0.5 to 7, and a molar ratio of (cobalt and nickel)/citric acid is 0.5 to 2. As for the hydrorefining catalyst obtained by this method, the activity of the catalyst is high, and the catalyst life is long.

Abstract: A method for hydrodesulfurization which comprises introducing partially desulfurized oil, which is a light oil fraction containing sulfur, and hydrogen to a reactor packed with a hydrodesulfurization catalyst, wherein the partially desulfurized oil has a sulfur content of 2000 ppm or less and preferably a polycyclic aromatic compound content of 3 wt % or more, wherein the amount of hydrogen sulfide contained in the partially desulfurized oil and hydrogen introduced to the reactor is 1.5 mol % or less with respect to that of the hydrogen introduced, and wherein the hydrodesulfurization catalyst comprises a carrier comprising a porous inorganic oxide and also comprises tungsten and one of nickel and cobalt as a metal component supported on the carrier. The method allows the production of a desulfurized light oil having a sulfur content of 50 ppm or less without the use of a special crude oil, and under operation conditions providing high productivity.

Abstract: Methoxyanthraquinones are produced from the corresponding nitroanthraquinones by reacting a nitroanthraquinone with methanol and an alkali in a reaction medium chiefly comprising methanol at a temperature of 50.degree.-130.degree. C under atmospheric or superatmospheric pressure in the presence of molecular oxygen wherein the dissolved oxygen concentration of the reaction medium is maintained at a value of at least 1 ppm.