Abstract: A method and apparatus for the combustion treatment of a toxic gas which forms microparticles by combustion are disclosed wherein the toxic gas is subjected to a combustion treatment in a specific combustion furnace where the combustion gas formed is brought into contact with an aqueous film flowing downwards on the inner wall of the furnace from the upper end portion thereof to the lower end portion thereof or with a cooled surface, and then optionally with aqueous droplets dispersed in the interior space of the furnace. The water captures the microparticles formed by combustion of the toxic gas and is discharged out of the furnace as a mixed flow with the combustion gas thus treated, and optionally the mixed flow is successively treated in a gas-liquid separator.

Abstract: A catalyst for dehalogenation of a halide comprising a corrosion-resistant ceramic or graphite having a surface area of 5.0 m.sup.2 /g or less and, supported thereon, at least one of a platinum group metal and a silicide thereof, and a method of dehalogenation of a halide using this catalyst.

Abstract: A method for the hydrogenation of coal tar pitch which comprises subjecting said coal tar pitch containing toluene insolubles to slight hydrogenation in the presence of a hydrogenation catalyst having carried on a refractory inorganic oxide carrier at least one member selected from the class consisting of elemental metals, belonging to Groups VI B and VIII in the Periodic Table and oxides and sulfides thereof, under the conditions of 280.degree. to 400.degree. C. of reaction temperature, 20 to 200 kg/cm.sup.2. G of hydrogen pressure, 0.1 to 10 hr.sup.-1 of LHSV, and 500 to 2,000 Nl/liter of hydrogen to liquid ratio, and a catalyst therefor. The "slight" hydrogenation is hydrogenation to a degree such that the difference of hydrogen to carbon atomic ratio between the untreated coal tar pitch and the hydrogenated coal tar pitch falls in the range of 0.03 to 0.5.

Abstract: A method of treating an aqueous sodium sulfide solution, such as white liquor in kraft pulping systems, for the oxidation of the sulfide with oxygen in the presence of a specific activated carbon catalyst which is (a) a particulate activated carbon catalyst having an average particle diameter of 0.2-4 mm, a pore volume of at least 0.25 cc/g in pores with diameters of not smaller than 100 .ANG. and a pore volume of at least 35% of the total pore volume in pores with diameters of not smaller than 100 .ANG. or (b) a fibrous activated carbon catalyst having a specific surface area of 300-2500 m.sup.2 /g and an outer surface area of 0.1-5 m.sup.2 /g.

Abstract: An improved method of preparing alumina, including a first stage in which an alumina hydrogel is formed from seed aluminum hydroxide, and a second stage in which the alumina hydrogel is processed for conversion into alumina.

Abstract: A catalyst for hydrotreating a heavy hydrocarbon oil containing asphaltenes comprises a porous carrier composed of one or more inorganic oxides of at least one element selected from among those of Groups II, III and IV of the Periodic Table, and at least one catalytic metal component composited with the carrier. The metal of the catalytic metal component is selected from among those of Groups VB, VIB, VIII and IB of the Periodic Table. The catalyst contains about 1 to 30% by weight of such catalytic metal component and has the following pore characteristics with regard to its pores having a diameter of 75 .ANG. or more: an average pore diameter APD of about 180 to 500 .ANG., a total pore volume PV, expressed in cc/g, being equal to or greater than a value X ##EQU1## the volume of pores with a diameter of about 180 to 500 .ANG. being at least about 0.2 cc/g, the volume of pores with a diameter of at least 1,500 .ANG. being not greater than about 0.03 cc/g, and a total surface area being at least about 60 m.

Abstract: A catalyst for the hydrotreatment of heavy hydrocarbon oils, which is prepared by supporting more than 2% by weight of VS.sub.x, wherein x represents about 1.1-1.59 in terms of an atomic ratio of S/V, on a substrate composed of a clay mineral which consists of magnesium silicate as a major component and having a double-chain structure and a process for preparing the catalyst are provided. The catalyst is prepared by accumulating the VS.sub.x on the substrate using a heavy hydrocarbon oil which contains particularly large amounts of vanadium and sulfur.

Abstract: A catalyst for hydrotreating a heavy hydrocarbon oil containing asphaltenes comprises a porous carrier composed of one or more inorganic oxides of at least one element selected from among those of Groups II, III and IV of the Periodic Table, and at least one catalytic metal component composited with the carrier. The metal of the catalytic metal component is selected from among those of Groups VB, VIB, VIII and IB of the Periodic Table. The catalyst contains about 1 to 30% by weight of such catalytic metal component and has the following pore characteristics with regard to its pores having a diameter of 75 .ANG. or more: an average pore diameter APD of about 180 to 500 .ANG., a total pore volume PV, expressed in cc/g, being equal to or greater than a value X ##EQU1## the volume of pores with a diameter of about 180 to 500 .ANG. being at least about 0.2 cc/g, the volume of pores with a diameter of at least 1,500 .ANG. being not greater than about 0.03 cc/g, and a total surface area being at least about 60 m.

Abstract: A catalyst for the hydrotreatment of heavy hydrocarbon oils, which is prepared by supporting more than 2% by weight of VS.sub.x, wherein x represents about 1.1-1.59 in terms of an atomic ratio of S/V, on a substrate composed of a clay mineral which consists of magnesium silicate as a major component and having a double-chain structure and a process for preparing the catalyst are provided. The catalyst is prepared by accumulating the VS.sub.x on the substrate using a heavy hydrocarbon oil which contains particularly large amounts of vanadium and sulfur.

Abstract: Improved .gamma.-alumina suitable for use as a catalyst carrier having high mechanical strength, a large specific surface area, and a substantially uniform pore size distribution in a relatively small portion of the pore size range below 500 A. Said alumina is produced by first establishing a seed aluminum hydroxide hydrogel having a pH of between 6 and 10 and then repetitively and sequentially adding an aluminum compound to adjust the pH to less than 5 or more than 11 to dissolve crystallites of aluminum hydroxide followed by addition of a neutralizing agent to return the hydrogel to the pH range from about 6 to 10 to cause pseudo-boehmite crystallites to grow. After a sufficient number of repetitions of said sequential addition, sparse aggregates of crystallites of the desired structure are formed. These are dried and calcined to produce the said alumina.

Abstract: This invention relates to a catalyst for hydrotreatment of hydrocarbons comprising one or more of metals selected from the group consisting of transition metals and metals of group IIb of the periodic table supported on sepiolite. More particularly it relates to a catalyst effective in the selective demetallization treatment of hydrocarbons.

Abstract: This invention relates to a catalyst for hydrotreatment of hydrocarbons comprising one or more of metals selected from the group consisting of transition metals and metals of group IIb of the periodic table supported on sepiolite. More particularly it relates to a catalyst effective in the selective demetallization treatment of hydrocarbons.

Abstract: A catalyst obtained by admixing red mud with alumina or/and an alumina-containing substance, optionally adjusting the water content of the admixture and/or adding an organic binder to the admixture, kneading and shaping the admixture into pellets having suitable size and shape, and calcining the pellets of 600.degree. C to 1,100.degree. C. The catalyst has a high compression strength and can, when used in the hydrodemetallization of hydrocarbons, achieve a high rate of demetallization and a low yield of low boiling fractions. The rate of demetallization is enhanced when the process is carried out using a hydrogen feed containing hydrogen sulfide.

Abstract: A catalyst obtained by admixing red mud with alumina or/and an alumina-containing substance, optionally adjusting the water content of the admixture and/or adding an organic binder to the admixture, kneading and shaping the admixture into pellets having suitable size and shape, and calcining the pellets at 600.degree. to 1,100.degree. C. The catalyst has a high compression strength and can, when used in the hydrodemetallization of hydrocarbons, achieve a high rate of demetallization and a low yield of low boiling fractions. The rate of demetallization is enhanced when the process is carried out using a hydrogen feed containing hydrogen sulfide.

Abstract: This invention relates to a catalyst for hydrotreatment of hydrocarbons comprising one or more of metals selected from the group consisting of transition metals and metals of group IIb of the periodic table supported on sepiolite. More particularly it relates to a catalyst effective in the selective demetallization treatment of hydrocarbons.