Apparatus and process for producing (meth)acrylic acid
AssigneeNippon Shokubai Co., Ltd.
InventorsSei Nakahara, Kazuhiko Sakamoto, Yukihiro Matsumoto, Kenji Sanada, Masatoshi Ueoka
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Abstract
The present invention provides an apparatus for producing (meth)acrylic acid and a process for producing (meth)acrylic acid with this apparatus wherein the apparatus enables to produce (meth)acrylic acid stably for a long period of time by effectively inhibiting the polymerization of (meth)acrylic acid in its production process (for example, in a reboiler). At least a part of the apparatus is made of a nickel-chromium-iron alloy with a molybdenum content of 3 to 20 mass %, but not including 3 mass %, or with a molybdenum content of 1 to 4 mass % and a copper content of 0.5 to 7 mass %.
Claims2
A method for minimizing polymerization of (meth)acrylic acid during the production of purified (meth)acrylic acid, comprising the steps of:
- a) providing an alloy, wherein the alloy comprises:
- (A) a nickel-chromium-iron alloy with a molybdenum content of 3 to 20 mass %, but not including 3 mass %;
- or
- (B) a nickel-chromium-iron alloy with a molybdenum content of 1 to 4 mass % and a copper content of 0.5 to 7 mass %;
- and then
- b) placing the alloy in a purification apparatus for producing purified (meth)acrylic acid, wherein the alloy forms a surface in the apparatus that comes into contact with (meth)acrylic acid at high temperature.
A method for minimizing polymerization of (meth)acrylic acid during the production of purified (meth)acrylic acid from crude (meth)acrylic acid, comprising the steps of:
- a) providing an alloy, wherein the alloy comprises:
- (A) a nickel-chromium-iron alloy with a molybdenum content of 3 to 20 mass %, but not including 3 mass %;
- or
- (B) a nickel-chromium-iron alloy with a molybdenum content of 1 to 4 mass % and a copper content of 0.5 to 7 mass %;
- and then
- b) placing the alloy in a purification apparatus for producing purified (meth)acrylic acid from crude (meth)acrylic acid, wherein the alloy forms a surface in the apparatus that comes into contact with (meth)acrylic acid at high temperature.
Dependencies are inferred from the claim text.