Abstract:
A process for the preparation of a composition comprising Al-, Ce- and Zr-oxides, which process comprises the steps of (a) preparing an aqueous solution of a mixture of metal salts of cerium, zirconium and aluminium, which aqueous solution optionally comprises one or more salts of the Rare Earth Metals other than cerium, (b) adding to the solution obtained a base at temperatures from 0° C. to 95° C. and precipitating the mixed metal salts in the form of hydroxides or oxy-hydroxides, (d) treating the aqueous suspension obtained in step (b) with a surfactant, and (e) isolating the precipitate obtained in step (d) and treating said precipitate at a temperature from 450° C. to 1200° C., which process is characterized in that the alumina content is in the range from 35 to 80% by weight, and the surface area (BET) of the composition obtained, measured according to DIN (Deutsche Industrie Norm) 66131 after calcining for 2 hours at 1100° C. is from 55 to 80 m2/g; or is at least 35 m2/g after calcining for 20 hours at 1100° C.; and a composition comprising Al-, Ce- and Zr-oxides, characterized in that the aluminium content, calculated as aluminium oxide is in the range from 35 to 80% by weight, and the surface area (BET) of the composition measured according to DIN (Deutsche Industrie Norm) 66131 for 2 hours at 1100° C. is from 55 to 80 m2/g, and/or is at least 35 m2/g after calcining for 20 hours at 1100° C. obtainable or obtained according such process.
Abstract:
Catalyst composition represented by the general formula REVO/S wherein RE is at least one of the group of rare earth metals Y, Ce, Pr, Nd, Sm, Gd, Tb, Dy, Er and Yb in an amount of up to 6.0 wt.-%; V is vanadium in an amount of 0.2-2.5 wt.-%; O is oxygen in an amount of up to 3.5 wt.-%; and S is a support containing TiO2 in an amount of at least 70 wt.-%, with the rest being WO3 and optionally SiO2. This catalyst composition shows high removal efficiencies for NOx even after aging at 750° C.
Abstract:
A catalyst composition comprising a vanadate represented by the formula XVO4/S, wherein XVO4 stands for a Bi-, Sb-, Ga- and/or Al-vanadate optionally in mixture with one or more rare earth metal-vanadates, or in mixture with one or more transition metal-vanadates, or in mixture with one or more transition metal-vanadates and one or more rare earth metal-vanadates, and S is a support comprising TiO2, optionally in combination with a dopant and a process for the preparation of such catalyst compositions.
Abstract:
A catalyst composition represented by the general formula XVO4/S wherein XVO4 stands for TransitionMetal-Vanadate, or a mixed TransitionMetal-/RareEarth-Vanadate, and S is a support comprising TiO2.
Abstract:
Imidazole and triazole derivatives of the general formula ##STR1## in which Ar denotes thienyl or denotes phenyl, biphenylyl or naphthyl, each of which is substituted by halogen, lower alkyl or lower alkoxy, R.sub.1 denotes hydrogen or lower alkyl, Alk denotes straight-chain or branched alkyl having 1 to 10 carbon atoms, Y denotes oxygen, sulfur, sulfinyl or sulfonyl, n denotes zero, 1 or 2, Z denotes oxygen, sulfur or sulfinyl, m denotes zero or 1, R.sub.3 denotes hydrogen, straight-chain or branched alkyl, cyclohexyl, or denotes phenyl which is optionally substituted by hydroxyl, halogen, trifluoromethyl, lower alkyl or lower alkoxy, or denotes biphenlyl, pyridyl or denotes naphthyl which is optionally substituted by halogen, X denotes CH or N, and R.sub.2 denotes hydrogen or lower alkyl, and their pharmaceutically acceptable acid addition salts for use as antimycotic agents in human and veterinary medicine.
Abstract:
A catalyst composition comprising a vanadate represented by the formula XVO4/S, wherein XVO4 stands for a Bi-, Sb-, Ga- and/or Al-vanadate optionally in mixture with one or more rare earth metal-vanadates, or in mixture with one or more transition metal-vanadates, or in mixture with one or more transition metal-vanadates and one or more rare earth met-al-vanadates, and S is a support comprising TiO2, optionally in combination with a dopant and a process for the preparation of such catalyst composi-tions.
Abstract:
The invention is directed to a process for the manufacture of a ceria based polishing composition, comprising (a) suspending an inorganic cerium salt or cerium hydroxide with a cerium content calculated as cerium oxide in the range of 50%-100% based on Total rare earth oxide (TREO) in an aqueous medium thereby obtaining an aqueous suspension, (b) treating said aqueous suspension with an acid or a salt of an acid selected from the group of HF, H3PO4 and H2SO4, thereby obtaining a solid suspended in said aqueous medium, (c) separating said solid from said aqueous medium, and (d) calcining the separated solid at a temperature between 750° C. and 1,200° C. and grinding the calcined solid to grain sizes in the range of 0.5 μm to 5.0 μm.
Abstract translation:本发明涉及一种制造二氧化铈基抛光组合物的方法,该方法包括:(a)以基于总稀土的50%-100%的范围,将计算为氧化铈的铈含量的无机铈盐或氢氧化铈悬浮 (TREO),由此获得水性悬浮液,(b)用酸或选自HF,H 3 PO 4和H 2 SO 4的酸的盐处理所述水性悬浮液,从而获得悬浮于所述水性溶液中的固体 介质,(c)从所述水性介质中分离所述固体,和(d)在750℃和1200℃之间的温度下煅烧分离的固体,并将煅烧后的固体研磨至0.5μm至5.0的范围内 μm。
Abstract:
The invention relates to a method for deposition of chromium layers as hard-chrome plating for protection against wear or corrosion and/or for decorative purposes and also an electroplating bath with which chromium layers of this type can be deposited. The invention also relates to hard-chrome surfaces produced accordingly.
Abstract:
Process for the preparation of alpha, omega-alkanedicarboxylic acids of the general formula I ##STR1## in which A is an alkylene radical having 4-14 C atoms by reacting a cycloalkene of the general formula II ##STR2## in which A has the abovementioned meaning with ozone in the presence of an inert solvent, catalytically hydrogenating the peroxide solution formed, followed by oxidation of the dialdehyde formed to the diacid of the formula I in the presence of an inert aprotic solvent.
Abstract:
A process for the preparation of a calcined mixed oxide comprising Al-, Ce- and Zr-oxides, comprising the steps of providing an aqueous slurry comprising hydroxides of cerium and zirconium, contacting the hydroxides of cerium and zirconium with an alumina precursor to obtain an aqueous suspension of solids, isolating the solids from the aqueous suspension and drying to obtain a solid composition, calcining the solid composition of step (c) at a temperature from 450° C. to 1200° C. for at least 1 hour to obtain a calcined mixed oxide.