摘要:
The invention relates to a dispersion of the type comprising particles of a rare earth compound, particularly a compound of cerium, an acid and an organic phase, characterized in further comprising an anti-oxidant agent which can particularly be selected from substituted derivatives of phenol, aromatic amines or tocopherols. Said dispersion may be used as additive for diesel fuel for internal combustion engines, in particular as additive for diesel for diesel engines.
摘要:
Engines equipped with an exhaust line fitted with a particulate filter, in which the particulates contained in the exhaust gas are trapped on such filter, and wherein the trapped particulates are periodically burned off, are operated by improvedly catalyzing the combustion of said particles utilizing a composition containing mixture of a lubricating oil and a colloidal dispersion as the engine-lubricating composition, which dispersion includes particles of at least one compound of at least one rare earth and an amphiphilic agent.
摘要:
The invention relates to a dispersion of the type comprising particles of a rare earth compound, particularly a compound of cerium, an acid and an organic phase, characterised in further comprising an anti-oxidant agent which can particularly be selected from substituted derivatives of phenol, aromatic amines or tocopherols. Said dispersion may be used as additive for diesel fuel for internal combustion engines, in particular as additive for diesel for diesel engines.;
摘要:
Solid catalysts suited for the fluidized/moving bed catalytic ammoxidation of alkanes comprise an active catalytic phase having the empirical formula (I): VSbaSnbTicFedEeOx (I) in which E is an element which provides an oxide of rutile structure or an element which, in combination with V, Sb, Sn, Ti, Fe and/or with another element E, provides a phase of rutile or trirutile structure, or a solid solution of rutile structure, a is a whole or fractional number equal to or greater than 0.5, b, c, d and e, independently, are each a whole or fractional number ranging from 0 to 100, and x is a whole or fractional number determined by the oxidation state of the other elements, such active catalytic phase being deposited onto/into particulates of a solid and porous oxidic support therefor, and are produced by (a) impregnating the solid and porous oxidic support with a solution, in at least one saturated alcohol, of compounds of vanadium and antimony and, optionally, compounds of tin and/or titanium and/or of iron and/or of element E, (b) contacting the solid and porous oxidic support thus impregnated with an aqueous buffer solution having a pH ranging from about 6 to 8, (c) separating the solids from such aqueous buffer solution and drying same, and (d) calcining the dried solids in two stages.
摘要:
The present invention relates to a process for the preparation of mixed vanadium, antimony and iron oxides and to their use as catalysts for the ammoxidation of alkanes. The process for the preparation of a mixed oxide defined above is characterized in that:respective vanadium, antimony and iron compounds are dissolved in at least one saturated alcohol or in water,the alcoholic .epsilon.olution or the aqueous solution thus obtained is brought into contact with an aqueous solution containing an ammonium salt, in order to precipitate the mixed oxide,the mixed oxide obtained is separated and calcined.
摘要:
The invention relates to a process for preparing 2-oxo-4-methylthiobutyric acid (I), its salts and its derivatives in which R represents a group chosen from COOH, COOR′, NH2, NHR′ or NR′R″, where R′ and R″ are chosen, independently of one another, from the group of linear or branched alkyl radicals having from 1 to 12 carbon atoms and cycloalkyl radicals having from 3 to 12 carbon atoms, according to which process but-3-ene-1,2-diol (II) is catalytically and selectively oxidized to give 2-oxobut-3-enoic acid (III) and methyl mercaptan is selectively condensed with 2-oxobut-3-enoic acid (III). 2-Oxo-4-methylthiobutyric acid (I), its salts and its derivatives are used as food supplement, in particular in animal nutrition.
摘要:
The invention relates to a process for preparing 2-oxo-4-methylthiobutyric acid (I), its salts and its derivatives in which R represents a group chosen from COOH, COOR′, NH2, NHR′ or NR′R″, where R′ and R″ are chosen, independently of one another, from the group of linear or branched alkyl radicals having from 1 to 12 carbon atoms and cycloalkyl radicals having from 3 to 12 carbon atoms, according to which process but-3-ene-1,2-diol (II) is catalytically and selectively oxidized to give 2-oxobut-3-enoic acid (III) and methyl mercaptan is selectively condensed with 2-oxobut-3-enoic acid (III). 2-Oxo-4-methylthiobutyric acid (I), its salts and its derivatives are used as food supplement, in particular in animal nutrition.
摘要:
A method for treating/purification a gas containing nitrogen oxides (NOx) includes conveying same through a NOx trap containing a composition based on a catalyst for oxidizing NOx into NO2 and a compound based on zirconium oxide and praseodymium oxide in a proportion of praseodymium oxide ranging from 5 wt. % to 50 wt. % of oxide; such compound may further include cerium oxide and the subject process is useful for treating the exhaust gas of a Diesel or lean mixture gasoline internal combustion engine.
摘要:
The present invention relates to a process for the treatment of exhaust gases from internal combustion engines operating with a fuel containing sulphur. This process is characterized in that use is made, as catalyst, of a composition based on a cerium oxide and on a zirconium oxide, in a cerium/zirconium atomic proportion of at least 1, and on at least one oxide chosen from yttrium, lanthanum and praseodymium oxide and which exhibits a specific surface, after calcination for 6 hours at 900 ° C., of at least 35 m2/g.
摘要:
Mixed oxide vanadium/antimony/titanium ammoxidation catalysts, particularly suited for the ammoxidation of alkanes and exhibiting X-ray diffraction spectra which are characteristic of a crystallographic phase of rutile TiO.sub.2, are prepared by (a) dissolving respective soluble compounds of vanadium, of antimony and of titanium in at least one saturated alcohol, (b) contacting the alcoholic solution thus obtained with water and precipitating the mixed oxide therefrom, and (c) separating and calcining the mixed oxide thus precipitated.