Abstract: A hydrodemetallizing catalyst for a hydrocarbon oil comprising a support and a catalytic component carried on the support, this catalyst having a surface, part of which has a coating layer composed of an inert substance having substantially no demetallizing activity, this coating layer allowing substantially no reaction fluid to permeate therethrough. This catalyst preferably has a reaction flow path through which a reaction fluid flows thereinside and is preferred to be, for example, in the form of a honeycomb structure or cylinder having one or a plurality of through holes.In the hydrodemetallization of heavy oils using the above hydrodemetallizing catalyst for a hydrocarbon oil, the sticking of the catalyst can be prevented and the spacing between catalyst particles can be maintained to thereby prevent a rapid increase of differential pressure, so that a continuous operation can be performed for a prolonged period of time.

Abstract: Terephthalic acid produced by oxidizing paraxylene can be obtained in the form of dried powder from the slurry containing terephthalic acid and acetic acid and/or water by using combination of a tubular type heater having at least one heating tube and a separation chamber in which the heating tube(s) open(s) at one end(s) thereof.Critical slurry concentrations for smooth operation are given.

Abstract: Reaction mother liquor of terephthalic acid production is treated to separate volatile component mainly composed of acetic acid and solid components composed of used catalyst or heavy metal salt(s), residual terephthalic acid and reaction by-products by using combination of a tubular type heater having at least one heating tube of a relatively small diameter and a separation chamber in which the heating tube(s) open(s) at one end thereof.

Abstract: A process of manufacturing a methane-containing gas, which comprises introducing a hydrocarbon feed material containing hydrocarbons having at least 2 carbon atoms per molecule and steam preheated to a temperature in the range of 250.degree.-600.degree. C into a steam reforming reactor (or reactors) packed with a nickel-containing catalyst comprising nickel and magnesia and further containing a copper-chromium mixture in the form of oxide or a copper-chromium-manganese mixture in the form of oxide and effecting steam reforming reaction of said hydrocarbons while maintaining the temperature of the catalyst bed of said reactor(s) in the range of 300.degree. to 600.degree. C.

Abstract: A process for manufacturing a methane-containing gas, which comprises introducing a hydrocarbon feed material containing hydrocarbons having at least 2 carbon atoms per molecule and steam preheated to a temperature in the range of 250.degree. to 600.degree. C into a steam reforming reactor (or reactors) packed with a catalyst comprising a nickel component and a magnesia component supported on a carrier, and effecting a steam reforming reaction of said hydrocarbons while maintaining the temperature of the catalyst bed of said reactor(s) in the range of 300.degree. to 600.degree. C.

Abstract: The present invention relates to a method of manufacturing a gas rich in methane by subjecting two varieties or more of hydrocarbons having more than 2 carbon atoms per molecule and different mean molecular weights to steam-reforming process comprising at least two stages, wherein a mixture consisting of hydrocarbons whose means molecular weight is relatively small and steam is introduced to the nickel-containing catalyst bed for the first stage at a temperature in the range of 350.degree. to 550.degree.C, and subsequently, the resulting product is mixed with hydrocarbons whose mean molecular weight is larger than that of the preceding hydrocarbon -- along with steam, if necessary -- and is introduced to the nickel-containing catalyst bed at a temperature in the range of 300.degree. to 550.degree.C for the second stage.