Abstract: Improved supported, mixed-metal oxide oxidation catalysts are prepared by conditioning a devolatilized catalyst precursor with an alcohol prior to calacining the precursor to a finished catalyst. For example, a promoted bismuth phosphomolybdate oxidation catalyst useful for converting propylene to acrolein demonstrates enhanced performance characteristics when the devolatilized catalyst precursor is subjected to boiling ethanol prior to calcining it to a finished catalyst.

Abstract: A novel process for producing oxygen-containing organic compounds with high selectivity and good yield by oxidizing organic compounds under mild conditions is provided, which process comprises using as a catalyst for the oxidation, a complex (M.sub.m X.sub.n.L.sub.l) consisting of a transition metal compound (M.sub.m X.sub.n) and an organic phosphorous compound (L) as a ligand, wherein M represents a transition metal belonging to group I, group IV.about.VII or iron group in group VIII of the periodic table; X represents an anion such as a halogen; ligand L represents an organic phosphorous compound; and m and n mean a number of the atomic valence of said transition metal (ion) M and said anion X, respectively, and l means a number of said ligand.

Abstract: In apparatuses for the preparation of phthalic anhydride and/or maleic anhydride by catalytic oxidation of naphthalene or o-xylene with air, reduced pressure is generated using liquid-jet pumps, and wash liquid is removed from the exit gas washer as a pump fluid for the liquid-jet pumps and is subsequently recycled to the exit gas washer.

Abstract: In the production of maleic anhydride, scale formation in an evaporator and pipes is a very difficult problem. By the process disclosed herein, scale formation in a maleic anhydride preparation apparatus can satisfactorily be prevented, and therefore, maleic anhydride preparation apparatus can be operated continuously for a long period. Further, it is also possible to significantly reduce the formation of fumaric acid. The process is that when conducting the concentration and dehydration of an aqueous solution of maleic acid, a small amount of hydrogen peroxide is added to the aqueous solution. Scale is formed by condensation of phenols and aldehydes, and quinones and aldehydes. Hydrogen peroxide added acts to oxidize aldehydes contained in the aqueous solution.

Abstract: A mixed oxide catalyst precursor comprising vanadium and phosphorus treated in finely divided form with phosphoric acid and water soluble compound of aluminum and/or boron to improve resistance to attrition.

Abstract: A process for the reactivation of a vanadium-phosphorus-oxygen catalyst promoted by metals selected from the group consisting of zinc, molybdenum, niobium, tungsten, uranium, cobalt and tin with alkyl esters of phosphoric acid and water is disclosed. The catalysts are useful for the manufacture of maleic anhydride from butane, butene, butadiene or benzene feedstock.

Abstract: A process for the production of maleic anhydride by catalytic air oxidation of hydrocarbons capable of being so oxidized at a temperature in the range of 300.degree.-450.degree. C.

Abstract: Large surface area oxidation catalysts suitable for converting C.sub.4 to C.sub.10 hydrocarbons to maleic anhydride are disclosed, comprising the oxides of vanadium, phosphorus and tin in combination with a crystalline silica having a surface area between 100 M.sup.2 /g to 450 M.sup.2 /g and wherein the vanadium has an average valence in the range of from 3.5 to 4.9.

Abstract: Maleic anhydride is separated off from gaseous reaction mixtures by a continuous process in which the gaseous reaction mixture containing the maleic anhydride is brought into contact with butanol, the gaseous substances obtained in this procedure are brought into contact with butyl maleate by a countercurrent method, and the liquid product is removed from the bottom.

Abstract: In a process for producing chemical substances comprising steps of cooling, condensing and solvent-absorbing the reaction product gas having a high temperature formed in a reactor, an absorption type refrigerator or an absorption type heat pump is driven by using, as the driving source, a heat source having such a temperature as not to be advantageous for the heat exchange in the process, which heat source has been taken out of the steps of cooling the reaction product gas, condensing it or solvent-absorbing it to obtain a refrigerant or a hot water having a temperature higher than the temperature of the heat source, and the refrigerant or the hot water is used as a cooling source or a heating source in the steps comprised in said process for producing chemical substances.

Abstract: A vanadium, phosphorus oxygen containing catalyst composition capable of partially oxidizing hydrocarbons (e.g., n-butane) to form a carboxylic anhydride (e.g., maleic anhydride), a process for preparing this catalyst, and a process for using this catalyst to form such anhydrides is disclosed. The catalyst composition is prepared by an organic heterogenous technique followed by a water treatment step and activation.

Abstract: The useful life of vanadium-phosphorus-oxygen (PVO) catalyst in fixed bed reactors can be substantially extended by treatment with a phosphorus compound followed by steam treatment. The PVO catalysts may be treated with steam after long periods (months) of only phosphorus compound treatment and the benefit of the present invention obtained or the phosphorus and steam treatments may be of only a few hours duration and sequential. In extending the useful life of the PVO catalyst according to the present invention, the temperature profile in the catalyst bed is restored to substantially the same profile as the fresh catalyst.

Abstract: A heterogeneous process for preparing a vanadium-phosphorus-oxygen containing catalyst for use in the preparation of carboxylic anhydrides is disclosed. This process employs an activation procedure in an air-hydrocarbon atmosphere.

Abstract: Oxidation catalysts having large surface areas and which are suitable for converting C.sub.4 to C.sub.10 hydrocarbons to maleic anhydride are disclosed, comprising the oxides of vanadium, phosphorus and tin in combination with hydrogen mordenite having a surface area between 100 M.sup.2 /g to 450 M.sup.2 /g and wherein the vanadium has an average valence in the range of from 3.5 to 4.95.

Abstract: Catalytic material is provided by a composition comprising the elements vanadium, non-water-contained hydrogen, phosphorus and non-water-contained oxygen. Freshly prepared catalytic material proxides relatively high yields upon its initial use in the catalytic oxidation of hydrocarbon feedstocks, such as n-butane and benzene to maleic anhydride.

Abstract: A system for producing phthalic anhydride by the catalytic oxidation of naphthalene, wherein the system is characterized by reduced capital and operating costs due to lower operating pressures.

Abstract: A system for producing phthalic anhydride by the catalytic oxidation of naphthalene, wherein without creating a significant pressure drop in the system substantially all of the catalyst particles are removed from the product stream before the product stream is sent to a battery of switch condensers for recovery of the phthalic anhydride.

Abstract: A process for reactivating a vanadium-containing oxidation catalyst, wherein the catalyst is treated first at from 100.degree. to 600.degree. C., with a volatile phosphorus compound in the presence of an oxygen-containing gas, and then at from 50.degree. to 600.degree. C. with sulfur trioxide or a mixture of a volatile sulfur compound and an oxygen-containing gas.