Abstract: A desulfurization system includes: a fuel supply part for supplying a hydrocarbon-based fuel containing water and a sulfur compound to a subsequent stage; and a desulfurization part for desulfurizing the above hydrocarbon-based fuel supplied from the above fuel supply part, wherein, in the above desulfurization part, the above hydrocarbon-based fuel is brought into contact at a temperature of 65 to 105° C. with a catalyst prepared by loading silver on an X-type zeolite.

Abstract: A catalyst is provided for hydrocracking paraffinic hydrocarbons which simultaneously the three requirements of high cracking activity and high selectivity of middle distillates as well as the low pour point of the resulting gas oil; and a process is provided for producing liquid hydrocarbons using the catalyst. The catalyst is characterized in that it comprises (a) a crystalline aluminosilicate and (b) an amorphous aluminosilicate at a weight ratio of 0.01<(a)/(b)<1.0. Furthermore, the catalyst is characterized in that it further comprises a group VIb metal and/or a group VIII metal.

Abstract: An object is to provide a reactor for hydrotreating which exhibits a total desulfurizing activity higher than that of the reactor according to the prior art, and which is reduced in the rate of lowering of the desulfurizing activity and therefore can keep the high desulfurizing activity over a long period, and to provide a process by the use of the reactor. A reactor for hydrotreating, which comprises at least four catalyst layers packed respectively with hydrotreating catalysts satisfying the relationship represented by the following formulae: Sn≦Sn+1, 1.15Vn≧Vn+1 wherein S represents the surface area per cubic meter of each hydrotreating catalyst; V represents the pore volume per cubic meter of catalyst; and wherein n is a natural number representing the order of each catalyst layer.

Abstract: An object is to provide a reactor for hydrotreating which exhibits a total desulfurizing activity higher than that of the reactor according to the prior art, and which is reduced in the rate of lowering of the desulfurizing activity and therefore can keep the high desulfurizing activity over a long period, and to provide a process by the use of the reactor. A reactor for hydrotreating, which comprises at least four catalyst layers packed respectively with hydrotreating catalysts satisfying the relationship represented by the following formulae: Sn≦Sn+1, 1.15Vn≧Vn+1 wherein S represents the surface area per cubic meter of each hydrotreating catalyst; V represents the pore volume per cubic meter of catalyst; and wherein n is a natural number representing the order of each catalyst layer.

Abstract: A hydrocracking catalyst for hydrocarbon oil, comprising a complex oxide with at least 2 different elements selected from Group 3b, Group 4a, Group 4b and Group 5b of the Periodic Table, zeolite having a solid Al-NMR spectrum wherein the ratio A/B of the peak area A in a chemical shift of -30 to 18 ppm to the peak area B in a chemical shift of 20-100 ppm is 0.01-0.39 and whose surface area of pores of diameter 10 angstrom or smaller constitutes 10-85% of the total surface area, and at least one metal selected from Group 6a and Group 8 of the Periodic Table. Also, a hydrocracking method characterized by hydrocracking of petroleum distillates with a boiling point of 250-600.degree. C. using the hydrocracking catalyst in the presence of hydrogen, under conditions with a reaction temperature of 100-800.degree. C., a reaction pressure of 3-30 MPa, an LHSV of 0.01-10 h.sup.-1 and a hydrogen/oil ratio of 100-2500 Nm.sup.3 /m.sup.3.

Abstract: The present invention provides a method for removing an iron content in a petroleum series mineral oil therefrom which comprises treating a petroleum series mineral oil fraction containing 5 ppm or more of the iron content by the use of a high gradient magnetic separator under conditions of the strength of a magnetic field being from 500 to 25,000 gauss, a temperature being from room temperature to 400.degree. C., and a linear velocity being 0.1 to 50 cm/second.