Abstract: A process for producing a hydrodesulfurization catalyst is disclosed, comprising impregnating an inorganic oxide carrier containing a crystalline aluminosilicate with a solution consisting of Group VI metal oxide, a Group VIII metal oxide, and phosphorus. Also disclosed is a process for deep hydrodesulfurization of a gas oil fraction using said catalyst to obtain gas oil having an extremely low sulfur content.

Abstract: Disclosed is a process for hydroconverting a heavy hydrocarbon oil in a reactor under high-temperature and high-pressure conditions,wherein said hydroconversion is carried out through using at least three desulfurization catalysts which each contains as active metals transition metals of Group VI and VIII in the Periodic Table supported on an alumina carrier and which have different SI of 40 or higher, 30 or higher and below 40, and lower than 30, respectively,and wherein said at least three catalysts are packed into the reactor in a descending order of SI from the inlet to the outlet of the reactor, with the proportion of the catalyst having SI of 40 or higher is at least 10% by volume, that of the catalyst having SI of 30 or higher and below 40 is at least 20% by volume, and that of the catalyst having SI of lower than 30 is at least 30% by volume.

Abstract: A catalyst composition for the hydrogenation of heavy hydrocarbon oil comprising at least one active ingredient for hydrogenation supported on a porous refractory oxide carrier and which has the following characteristics:(1) the mean pore diameter of the pores thereof is in the range of 130 to 250 .ANG.;(2) the volume of pores having a pore diameter within .+-.30 .ANG. of the mean pore diameter is in the range of from not less than 30% to less than 60% of the total volume of the pores;(3) the volume of pores having a pore diameter of not larger than 80 .ANG. is not more than 13% of the total volume of the pores;(4) the volume of pores having a pore diameter of not smaller than 350 .ANG. is not more than 25% of the total volume of the pores; and(5) the ratio (mm.sup.2 /mm.sup.3) of the outer surface of a molded catalyst particle to the volume thereof is in the range of 3 to 8.

Abstract: A process for the production of a p-vinyl phenol polymer which comprises polymerizing p-vinyl phenol in the presence of (a) phenols that do not have any unsaturated side chains and (b) a polymerization accelerator; wherein water and iron are present in the polymerization reaction system so as to control formation of low molecular weight by-products which damage properties of the resulting p-vinyl phenol polymer.

Abstract: A process for the production of p-vinyl phenol by the dehydrogenation of p-ethyl phenol in a gaseous phase in the presence of a catalyst and a diluent wherein the dehydrogenation of p-ethyl phenol is effected with phenol and/or p-cresol being present in the reaction system in an amount of 5 to 50 wt % of the amount of p-ethyl phenol.

Abstract: A process for producing terephthalic acid of high quality suitable for use in direct polymerization comprising oxidizing a para-dialkylbenzene and/or an oxidized intermediate thereof in the liquid phase with molecular oxygen or a molecular oxygen-containing gas in the presence of an oxidation catalyst containing a heavy metal in a lower aliphatic carboxylic acid solvent, the reaction being carried out in the presence of a specified amount of a phenol. Polyesters prepared from the resulting terephthalic acid have good color.

Abstract: A method for recovering a heavy metal oxidation catalyst used in a liquid-phase oxidation process for producing terephthalic acid from the residue of the reaction mother liquor by stirring the residue together with water in the presence of molecular oxygen and a sulfur compound, subjecting the extracted mixture to a solid-liquid separation to separate the solid impurities, adding the aqueous solution containing the oxidation catalyst to an alkali metal or ammonium carbonate or an aqueous solution of an alkali metal or ammonium carbonate while maintaining the temperature of the system at about 26.degree.C to 70.degree.C, and recovering the heavy metal catalyst as a carbonate precipitate having high purity and good filterability and washability.