An apparatus for efficiently removing the exuded substance and/or the attached substance on the surface of a catalyst (catalyst surface substance) from the catalyst is provided. The apparatus comprising a main body, the apparatus for removing a catalyst surface substance present on a surface of a catalyst from the catalyst by bringing a gas flow into contact with the catalyst housed in the main body, wherein a gas flow length in a flow direction of the gas flow is 55 mm or more, and an average flow velocity of the gas flow is 80 m/s or more and 500 m/s or less in terms of a linear velocity at 15 C. and 1 atm.

Disclosed is a modified propene dehydrogenation (PDH) system and method for producing one or more chemical products from propane as the sole feed stock. The modified PDH system includes a reactor for converting propane into a stream of propene, hydrogen, and waste gas. It further includes a de-ethanizer stripper downstream of the PDH reactor for separating the reactor output gas into a stream of propene as one of an end product or an intermediate product, and a stream of hydrogen and waste gas. The modified PDH system also includes a hydrogen recovery unit disposed downstream of the de-ethanizer stripper system for separating the stream of waste gas and hydrogen into separate streams of waste gas, and hydrogen, with the hydrogen stream being one of an end product or an intermediate product. The modified PDH system can produce propene, hydrogen, ammonia, acrylonitrile, urea, or methanol.

Disclosed is a modified propene dehydrogenation (PDH) system and method for producing one or more chemical products from propane as the sole feed stock. The modified PDH system includes a reactor for converting propane into a stream of propene, hydrogen, and waste gas. It further includes a de-ethanizer stripper downstream of the PDH reactor for separating the reactor output gas into a stream of propene as one of an end product or an intermediate product, and a stream of hydrogen and waste gas. The modified PDH system also includes a hydrogen recovery unit disposed downstream of the de-ethanizer stripper system for separating the stream of waste gas and hydrogen into separate streams of waste gas, and hydrogen, with the hydrogen stream being one of an end product or an intermediate product. The modified PDH system can produce propene, hydrogen, ammonia, acrylonitrile, urea, or methanol.

The present invention provides a method for producing a catalyst to be used for a gas-phase catalytic ammoxidation reaction of propane, the method comprising a preparation step of dissolving or dispersing a raw material to thereby obtain a prepared raw material liquid, a first drying step of drying the prepared raw material liquid to thereby obtain a dried material, a calcination step of calcining the dried material to thereby obtain a composite oxide having a predetermined composition, an impregnation step of impregnating the composite oxide with a solution containing at least one specific element selected from the group consisting of tungsten, molybdenum, tellurium, niobium, vanadium, boron, bismuth, manganese, iron, antimony, phosphorus and rare earth elements to thereby obtain an impregnated composite oxide, and a second drying step of drying the impregnated composite oxide, wherein at least one of the impregnation step o and the second drying step is a step of impregnating the composite oxide or drying the impregnated composite oxide while stirring by a specific stirring power.

The present invention provides a method for producing a catalyst to be used for a gas-phase catalytic ammoxidation reaction of propane, the method comprising a preparation step of dissolving or dispersing a raw material to thereby obtain a prepared raw material liquid, a first drying step of drying the prepared raw material liquid to thereby obtain a dried material, a calcination step of calcining the dried material to thereby obtain a composite oxide having a predetermined composition, an impregnation step of impregnating the composite oxide with a solution containing at least one specific element selected from the group consisting of tungsten, molybdenum, tellurium, niobium, vanadium, boron, bismuth, manganese, iron, antimony, phosphorus and rare earth elements to thereby obtain an impregnated composite oxide, and a second drying step of drying the impregnated composite oxide, wherein at least one of the impregnation step o and the second drying step is a step of impregnating the composite oxide or drying the impregnated composite oxide while stirring by a specific stirring power.

The present invention provides a method for producing an oxide catalyst comprising Mo, V, Sb, and Nb for use in a gas-phase catalytic oxidation reaction or a gas-phase catalytic ammoxidation reaction of propane or isobutane, the method comprising: a preparation step of preparing a first aqueous mixed solution containing Mo, V, and Sb; a mixing step of mixing the first aqueous mixed solution with a support raw material comprising silica sol, and a Nb raw material to obtain a second aqueous mixed solution; a drying step of drying the second aqueous mixed solution to obtain a dry powder; and a calcination step of calcining the dry powder to obtain the oxide catalyst, wherein the support raw material comprises 25% by mass or more, based on SiO.sub.2, of the silica sol having an average primary particle size of 3.0 nm or larger and smaller than 11 nm based on a total amount of the support raw material, and the silica sol comprises 55% or more of silica sol particles having a primary particle size of smaller than 11 nm.

The present invention provides a method for producing an oxide catalyst comprising Mo, V, Sb, and Nb for use in a gas-phase catalytic oxidation reaction or a gas-phase catalytic ammoxidation reaction of propane or isobutane, the method comprising: a preparation step of preparing a first aqueous mixed solution containing Mo, V, and Sb; a mixing step of mixing the first aqueous mixed solution with a support raw material comprising silica sol, and a Nb raw material to obtain a second aqueous mixed solution; a drying step of drying the second aqueous mixed solution to obtain a dry powder; and a calcination step of calcining the dry powder to obtain the oxide catalyst, wherein the support raw material comprises 25% by mass or more, based on SiO.sub.2, of the silica sol having an average primary particle size of 3.0 nm or larger and smaller than 11 nm based on a total amount of the support raw material, and the silica sol comprises 55% or more of silica sol particles having a primary particle size of smaller than 11 nm.

The present invention provides a method for producing an oxide catalyst comprising Mo, V, Sb, and Nb for use in a gas-phase catalytic oxidation reaction or a gas-phase catalytic ammoxidation reaction of propane or isobutane, the method comprising: a preparation step of preparing a first aqueous mixed solution containing Mo, V, and Sb; a mixing step of mixing the first aqueous mixed solution with a support raw material comprising silica sol, and a Nb raw material to obtain a second aqueous mixed solution; a drying step of drying the second aqueous mixed solution to obtain a dry powder; and a calcination step of calcining the dry powder to obtain the oxide catalyst, wherein the support raw material comprises 25% by mass or more, based on SiO.sub.2, of the silica sol having an average primary particle size of 3.0 nm or larger and smaller than 11 nm based on a total amount of the support raw material, and the silica sol comprises 55% or more of silica sol particles having a primary particle size of smaller than 11 nm.

The present invention provides a method for producing an oxide catalyst comprising Mo, V, Sb, and Nb for use in a gas-phase catalytic oxidation reaction or a gas-phase catalytic ammoxidation reaction of propane or isobutane, the method comprising: a preparation step of preparing a first aqueous mixed solution containing Mo, V, and Sb; a mixing step of mixing the first aqueous mixed solution with a support raw material comprising silica sol, and a Nb raw material to obtain a second aqueous mixed solution; a drying step of drying the second aqueous mixed solution to obtain a dry powder; and a calcination step of calcining the dry powder to obtain the oxide catalyst, wherein the support raw material comprises 25% by mass or more, based on SiO.sub.2, of the silica sol having an average primary particle size of 3.0 nm or larger and smaller than 11 nm based on a total amount of the support raw material, and the silica sol comprises 55% or more of silica sol particles having a primary particle size of smaller than 11 nm.

The present invention provides a method for producing an oxide catalyst comprising Mo, V, Sb, and Nb for use in a gas-phase catalytic oxidation reaction or a gas-phase catalytic ammoxidation reaction of propane or isobutane, the method comprising: a preparation step of preparing a first aqueous mixed solution containing Mo, V, and Sb; a mixing step of mixing the first aqueous mixed solution with a support raw material comprising silica sol, and a Nb raw material to obtain a second aqueous mixed solution; a drying step of drying the second aqueous mixed solution to obtain a dry powder; and a calcination step of calcining the dry powder to obtain the oxide catalyst, wherein the support raw material comprises 25% by mass or more, based on SiO.sub.2, of the silica sol having an average primary particle size of 3.0 nm or larger and smaller than 11 nm based on a total amount of the support raw material, and the silica sol comprises 55% or more of silica sol particles having a primary particle size of smaller than 11 nm.