Abstract: A method for producing acrylic acid by absorbing acrylic acid at a high ratio and obtaining an acrylic acid-containing solution of high concentration is provided. This method comprises a step of circulating part of a discharged gas from an absorption step of acrylic acid to the reactor and discarding the remainder to the out side of system while the gas is cooled before circulation to the reactor. By the method, the acrylic acid-containing solution of high concentration is obtained due to decrease of an acrylic acid loss.

Abstract: A method for producing acrylic acid by absorbing acrylic acid at a high ratio and obtaining an acrylic acid-containing solution of high concentration is provided. This method comprises a step of circulating part of a discharged gas from an absorption step of acrylic acid to the reactor and discarding the remainder to the out side of system while the gas is cooled before circulation to the reactor. By the method, the acrylic acid-containing solution of high concentration is obtained due to decrease of an acrylic acid loss.

Abstract: A method for the production of acrylic acid of high concentration by absorbing acrylic acid with high absorption ratio of acrylic acid is provided. In a method for producing acrylic acid by a procedure comprising a step of catalytic gas phase oxidation reaction and a step of absorbing the acrylic acid-containing gas, while a low boiling substance-containing solution is introduced into the absorption column via a portion different from the top of the column.

Abstract: A method for producing acrylic acid by absorbing acrylic acid at a high ratio and obtaining an acrylic acid-containing solution of high concentration is provided. This method comprises a step of circulating part of a discharged gas from an absorption step of acrylic acid to the reactor and discarding the remainder to the out side of system while the gas is cooled before circulation to the reactor. By the method, the acrylic acid-containing solution of high concentration is obtained due to decrease of an acrylic acid loss.

Abstract: A method for producing acrylic acid by using an acrylic acid-containing solution of high concentration without azeotropic distillation is provided. This method of producing acrylic acid comprises introducing an acrylic acid-containing gas obtained by catalytic gas phase oxidation reaction into an absorption column and supplying the acrylic acid-containing solution to crystallization step thereby separating the solution into acrylic acid and residual mother liquid, and distilling at least part of the residual mother liquid and circulating the distillate obtained by the distillation to the absorption column.

Abstract: A method for producing acrylic acid from an acrylic acid-containing solution of high concentration without performing azeotropic distillation is provided. This method of producing acrylic acid comprises steps of absorbing acrylic acid-containing gas, distilling the acrylic acid-containing solution without using an azeotropic solvent thereby obtaining crude acrylic acid as a column bottom stream and/or a column side stream, and supplying the crude acrylic acid to a crystallizing step and melt crystallizing the crude acrylic acid thereby obtaining purified acrylic acid.

Abstract: A method for the production of acrylic acid of high concentration by absorbing acrylic acid with high absorption ratio of acrylic acid is provided. In a method for producing acrylic acid by a procedure comprising a step of catalytic gas phase oxidation reaction and a step of absorbing the acrylic acid-containing gas, while a low boiling substance-containing solution is introduced into the absorption column via a portion different from the top of the column.

Abstract: A method for producing acrylic acid from an acrylic acid-containing solution of high concentration without performing azeotropic distillation is provided. This method of producing acrylic acid comprises steps of absorbing acrylic acid-containing gas, distilling the acrylic acid-containing solution without using an azeotropic solvent thereby obtaining crude acrylic acid as a column bottom stream and/or a column side stream, and supplying the crude acrylic acid to a crystallizing step and melt crystallizing the crude acrylic acid thereby obtaining purified acrylic acid.

Abstract: A method for producing acrylic acid by using an acrylic acid-containing solution of high concentration without azeotropic distillation is provided. This method of producing acrylic acid comprises introducing an acrylic acid-containing gas obtained by catalytic gas phase oxidation reaction into an absorption column and supplying the acrylic acid-containing solution to crystallization step thereby separating the solution into acrylic acid and residual mother liquid, and distilling at least part of the residual mother liquid and circulating the distillate obtained by the distillation to the absorption column.

Abstract: A method for producing acrylic acid by absorbing acrylic acid at a high ratio and obtaining an acrylic acid-containing solution of high concentration is provided. This method comprises a step of circulating part of a discharged gas from an absorption step of acrylic acid to the reactor and discarding the remainder to the out side of system while the gas is cooled before circulation to the reactor. By the method, the acrylic acid-containing solution of high concentration is obtained due to decrease of an acrylic acid loss.