Abstract:
Disclosed are a catalyst for selective catalytic reduction of nitrogen oxides and a method for preparing the same. Useful for the removal of nitrogen oxides is a catalyst prepared using spent catalysts having been absorbed with vanadium, nickel and sulfur in the hydro-desulfurization line of an oil refinery in which a catalyst for the hydro-desulfurization contains molybdenum, iron, cobalt and silicon on the alumina support in accordance with the present invention. The present catalyst can remove nitrogen oxides at a level of 90% or higher, exhibiting a 10% or more increase in efficiency of the catalyst performance. Additionally, the catalyst can increase the efficiency of spent catalyst reclamation by 250%.
Abstract:
The present invention pertains to a process for sulfiding a catalyst composition comprising at least one hydrogenation metal component of Group VI and/or Group VIII of the Periodic Table, and an S-containing organic additive wherein the catalyst composition is contacted in two steps with hydrogen and a sulfur-containing compound in the gaseous phase, with the first step being performed at a temperature which is lower than that of the second step. Catalysts sulfided by the process according to the invention show a higher activity than the same catalysts which have been sulfided in a one-step process. It is preferred to carry out the process according to the invention ex situ, where it solves the problem of difficult start-up and the formation of undesirable side products in the hydrotreating unit. The S-containing organic additive preferably is a mercapto-compound, more preferably a mercaptocarboxylic acid represented by the general formula HSnullR1-COOR, wherein R1 stands for a divalent hydrocarbon group with 1null about 10 carbon atoms and R stands for a hydrogen atom, an alkali metal, an alkaline earth metal, ammonium, or a linear or branched alkyl group having 1 to about 10 carbon atoms. The invention also pertains to the catalyst made by the above process and a process for hydrotreating a hydrocarbon feed by contacting the feed with the catalyst at hydrotreating conditions.
Abstract:
A gel composition substantially contained within the pores of a solid material is disclosed for use as a catalyst or as a catalyst support in dehydrogenation and dehydrocyclization processes.
Abstract:
This invention provides a new catalyst for purification of diesel engine exhaust gas comprising a carrier of at least one sulfur-resistant refractory oxide and at least one catalytic metal, wherein at least one solid acid and/or sulfuric acid is carried on the carrier by adding at least one precursor of said solid acid and/or sulfuric acid during the preparation of the carrier, and preparation thereof. The catalyst of this invention is thermally and chemically durable and can effectively remove particulate matters, hydrocarbons and nitrogen oxides contained in the diesel engine exhaust gas at low temperatures.
Abstract:
One aspect of the present invention relates to a catalytic compound of anion-modified metal oxides doped with metal ions. Another aspect of the present invention relates to a method of isomerizing an alkane or alkyl moiety.
Abstract:
The invention concerns a method for sulphurizing catalysts for hydrotreating of hydrocarbon feedstocks. The invention is characterised in that it consists in sulphurizing the catalyst in two steps: the first step consisting in sulphurization with tertiary mercaptan in the absence of hydrogen, and the second step, carried out consecutively in the same reactor, consisting of sulphurization with another sulphurizing agent in the presence of hydrogen. The catalysts thus sulphurized prove to be more active than those sulphurized by only the second step.
Abstract:
The present invention provides a concentration distribution for a platinum group metal component in a catalyst with which catalyst activity can be increased, and to provide a method for supporting a platinum group metal with which this concentration distribution can be achieved. The present invention is a solid acid catalyst that comprises porous catalyst pellets exhibiting solid acid characteristics, and a platinum group metal component supported by these catalyst pellets, and that is used in an acid-catalyzed reaction, in which a quotient of dividing the standard deviation of concentration in a platinum group metal component concentration distribution in the catalyst by an average concentration is 0.4 or less. The method for preparing. this catalyst comprises a step of preparing a support solution containing a platinum group metal as a cation, and a step of impregnating crystalline, porous catalyst pellets exhibiting solid acid characteristics with this support solution. The present invention also provides a method for isomerizing a hydrocarbon, wherein a solid acid catalyst is brought into contact with a hydrocarbon including at least 70 wt % of a saturated hydrocarbon component having 4 to 10 carbon atoms.
Abstract:
A photocatalyst which comprises an oxysulfide containing at least one transition metal; a preferable photocatalyst which also comprises a rare earth element such as Sm in addition to the above and wherein the transition metal is at least one selected from the group consisting of Ti and Nb; a more preferable photocatalyst which further comprises a promoter comprising a transition metal such as Pt loaded on each of the above photocatalyst; and a catalyst for use in the decomposition of water by a light which comprises one of the above oxysulfide photocatalysts.
Abstract:
A practical catalyst exhibiting especially high CO shift reaction activity in a low temperature region where CO is favorably converted to H2 in equilibrium includes a carrier which is composed of titania as a main component, a noble metal which is supported on the carrier, and a sulfur-containing material which adheres to the carrier. The titania carrier to which the sulfur-containing material adheres exhibits high solid acid strength, and accordingly acts to absorb electrons from noble metal so that noble metal becomes partially oxidized. This results in the CO adsorbing ability decreasing to restrain poisoning of noble metal due to CO, whereby the CO shift reaction activity in a low temperature region is improved.
Abstract:
Ruthenium sulfide catalyst and gas diffusion electrodes incorporating the same for reduction of oxygen in industrial electrolyzers which catalyst is highly resistant to corrosion making it useful for oxygen-depolarized aqueous hydrochloric acid electrolysis.