Abstract: The production process of the invention comprises a first step of hydrodesulfurizing of catalytically-cracked gasoline so as to result in an olefin hydrogenation rate of no greater than 25 mol % in the catalytically-cracked gasoline, a total sulfur content of no greater than 20 ppm by weight based on the product oil weight, a sulfur content derived from thiophenes and benzothiophenes of no greater than 5 ppm by weight and a sulfur content derived from thiacyclopentanes of no greater than 0.1 ppm by weight, and a second step of further hydrodesulfurizing of the product oil obtained by the first step so as to result in a total of no greater than 30 mol % for the olefin hydrogenation rate in the first step and the olefin hydrogenation rate in the second step, a total sulfur content of no greater than 10 ppm by weight based on the product oil weight, and a sulfur content derived from thiols of no greater than 5 ppm by weight.

Abstract: The production process of the invention comprises a first step of hydrodesulfurizing of catalytically-cracked gasoline so as to result in an olefin hydrogenation rate of no greater than 25 mol % in the catalytically-cracked gasoline, a total sulfur content of no greater than 20 ppm by weight based on the product oil weight, a sulfur content derived from thiophenes and benzothiophenes of no greater than 5 ppm by weight and a sulfur content derived from thiacyclopentanes of no greater than 0.1 ppm by weight, and a second step of further hydrodesulfurizing of the product oil obtained by the first step so as to result in a total of no greater than 30 mol % for the olefin hydrogenation rate in the first step and the olefin hydrogenation rate in the second step, a total sulfur content of no greater than 10 ppm by weight based on the product oil weight, and a sulfur content derived from thiols of no greater than 5 ppm by weight.

Abstract: A hydrodesulfurization catalyst used for hydrodesulfurization of catalytically cracked gasoline comprises a support composed mainly of alumina modified with an oxide of at least one metal selected from the group consisting of iron, chromium, cobalt, nickel, copper, zinc, yttrium, scandium and lanthanoid-based metals, with at least one metal selected from the group consisting of Group 6A and Group 8 metals loaded as an active metal on the support. Hydrogenation of olefins generated as by-products during hydrodesulfurization of the catalytically cracked gasoline fraction, as an important constituent base of gasoline, can be adequately inhibited to maintain the octane number, while sufficiently reducing the sulfur content of the hydrodesulfurized catalytically cracked gasoline fraction.

Abstract: A hydrodesulfurization catalyst used for hydrodesulfurization of catalytically cracked gasoline comprises a support composed mainly of alumina modified with an oxide of at least one metal selected from the group consisting of iron, chromium, cobalt, nickel, copper, zinc, yttrium, scandium and lanthanoid-based metals, with at least one metal selected from the group consisting of Group 6A and Group 8 metals loaded as an active metal on the support. Hydrogenation of olefins generated as by-products during hydrodesulfurization of the catalytically cracked gasoline fraction, as an important constituent base of gasoline, can be adequately inhibited to maintain the octane number, while sufficiently reducing the sulfur content of the hydrodesulfurized catalytically cracked gasoline fraction.

Abstract: A hydrogenation region in a fixed bed reactor is defined with a first, a second and a third hydrogenation zones sequentially from the entrance of the reactor, and a sulfur-containing diesel gas oil feedstock is passed through the first, second and third hydrogenation zones sequentially under conditions of a temperature of 320 to 420° C., a pressure of 5 to 15 MPa, an LHSV of 0.

Abstract: Diesel gas oil feedstock with 1-3 wt % sulfur can be hydrodesulfurized to a diesel gas oil with 0.05 wt % or less sulfur and a Saybolt color of +20 or higher, by defining a hydrogenation region in a fixed bed reactor with a first hydrogenation zone for dibenzothiophene, 1-, 2- and 3-methyldibenzothiophenes, a second hydrogenation zone for 4-methyldibenzothiophene and 4,6-dimethyldibenzothiophene and a third hydrogenation zone for thiols, sulfides and other sulfur-containing substances.

Abstract: A process for hydrodesulfurization of a sulfur-containing petroleum hydrocarbon diesel gas oil comprising; hydrodesulfurizing a sulfur-containing petroleum hydrocarbon diesel gas oil feedstock, separating the hydrodesulfurized diesel gas oil feedstock into light and heavy fractions by distillation, hydrodesulfurizing further the separated heavy fraction, and mixing the further hydrodesulfurized heavy fraction and the separated light fraction into the hydrocarbon diesel gas oil.

Abstract: A method of hydrodesulfurizing a catalytic cracked gasoline which comprises providing a presulfided catalyst modified with a basic organic nitrogen compound and contacting the catalytic cracked gasoline with the catalyst.

Abstract: A process for desulfurizing catalytically cracked gasoline containing sulfur compounds and olefin components, which comprises the steps of:1) first desulfurizing the catalytically cracked gasoline in the presence of a hydrodesulfurization catalyst at a desulfurization rate of 60 to 90%, a reaction temperature of 200 to 350.degree. C., a hydrogen partial pressure of 5 to 30 kg/cm.sup.2, a hydrogen/oil ratio of 500 to 3,000 scf/bbl, and a liquid hourly space velocity of 2 to 10 1/hr, said first desulfuriing step comprising supplying a feed having a hydrogen sulfide vapor concentration of not more than 0.1% by volume, and2) next desulfurizing the treated oil obtained in the first step in the presence of a hydrodesulfurization catalyst at a desulfurization rate of 60 to 90%, a reaction temperature of 200 to 300.degree. C., a hydrogen partial pressure of 5 to 15 kg/cm.sup.

Abstract: A catalytically cracked gasoline feedstock is desulfurized under reaction conditions of a hydrogen feed rate measured at the reactor inlet of from 1 to 5 mols per mol of the feedstock oil and of from 5 to 50 mols per mol of the olefin components contained in the feedstock oil, a reaction temperature of from 200.degree. to 300.degree. C., a total pressure inside the reactor of from 10 to 20 kg/cm.sup.2 G, and a liquid hourly space velocity of from 2 to 8 l/hr, and using a catalyst which comprises a support mainly comprising alumina and having a surface area of 200 m.sup.2 /g or larger, wherein MoO.sub.3 in an amount of from 10 to 20 wt % and CoO in an amount of from 3 to 6 wt % in terms of inner content are fixed to the support, and the weight ratio of MoO.sub.3 to CoO is from 2.5 to 4.5.

Abstract: Disclosed is an emulsified alkenylsuccinic acid sizing agent useful for acid papermaking. The sizing agent has a solid concentration of at least 25% by weight and comprises an alkenylsuccinic acid which is the reaction product of a branched internal olefin and maleic anhydride and which has been dispersed in water by an emulsifying and dispersing agent comprising polyvinyl alcohol. The sizing agent results in good storage stability and has an excellent sizing effect at a low addition ratio immediately after completion of high-temperature papermaking and over a wide pH range.

Abstract: An alkenylsuccinic anhydride type paper sizing agent composition which causes little contamination of a paper machine and exhibits an excellent sizing effect is provided.The paper sizing agent composition contains addition reaction products obtained from an addition reaction between a straight-chain internal olefin comprising 16 to 20 carbon atoms and maleic anhydride, any unreacted olefin and maleic anhydride having been removed from said addition reaction products; said addition reaction products comprising as a main component alkenylsuccinic anhydride (1:1 adduct) represented by formula (I): ##STR1## wherein both of R and R' are alkyl groups or either one of R and R' is an alkyl group while the other is a hydrogen atom; and a 1:2 adduct (2 moles maleic anhydride per mole of olefin), and a decarbonated product of said 1:2 adduct in a total amount, based on said addition reaction products, of from about 7 to about 12 mol%.

Abstract: The present invention relates to a sizing agent which exerts excellent sizing efficiency even under severe conditions, namely, at an elevated temperature in the papermaking step, or at high conditions with a limited aluminum sulfate addition.The sizing agent for paper of the present invention is derived from i) dehydration condensation of an alkenylsuccinic anhydride and an organic carboxylic acid with a polyalkylene polyamine and ii) saponification of the remaining carboxyl groups with alkali following the dehydration condensation. More particularly, the present invention relates to a water-soluble sizing agent which is obtained by mixing an alkenylsuccinic anhydride with 1 to 20 times by molar equivalent, based on said alkenylsuccinic anhydride, as much as an organic carboxylic acid, adding 0.1 to 2.0 times by molar equivalent, based on said alkenylsuccinic anhydride, as much as a polyalkylene polyamine thereto so as to perform dehydration condensation.

Abstract: A sizing agent for paper making is described, comprising (A) a reaction product obtained by an addition reaction of an olefin having 14 to 20 carbon atoms or a mixture thereof with maleic anhydride and (B) one or more emulsifiers selected from polyoxyalkylene aralkylaryl ether phosphoric acid esters or salts thereof.