The present invention generally relates to processes for converting acrylate esters or a derivative thereof to difluoropropionic acid or a derivative thereof. This process is generally performed using fluorine gas in a hydrofluorocarbon solvent.

In one embodiment, the present invention provides a method, comprising: a. adding an effective amount of at least one compound selected from the group consisting of a substituted catechol, nitroxide free radicals, a compound of Formula 2, 4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl, phenol, hydroxylamine, and phenylene diamine to a solution of a monomer selected from the group consisting of acrylonitrile, acrylic acid, vinylacetate, acrylates and acrolein; b. placing the monomer solution containing the at least one compound in a pressure vessel, pressurizing the pressure vessel and removing oxygen from the pressure vessel; and c. heating the monomer solution containing the at least one compound, wherein the at least one compound inhibits fouling by preventing polymerization of the monomer.

In one embodiment, the present invention provides a method, comprising: a. adding an effective amount of at least one compound selected from the group consisting of a substituted catechol, nitroxide free radicals, a compound of Formula 2, 4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl, phenol, hydroxylamine, and phenylene diamine to a solution of a monomer selected from the group consisting of acrylonitrile, acrylic acid, vinylacetate, acrylates and acrolein; b. placing the monomer solution containing the at least one compound in a pressure vessel, pressurizing the pressure vessel and removing oxygen from the pressure vessel; and c. heating the monomer solution containing the at least one compound, wherein the at least one compound inhibits fouling by preventing polymerization of the monomer.

In one embodiment, the present invention provides a method, comprising: a. adding an effective amount of at least one compound selected from the group consisting of a substituted catechol, nitroxide free radicals, a compound of Formula 2, 4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl, phenol, hydroxylamine, and phenylene diamine to a solution of a monomer selected from the group consisting of acrylonitrile, acrylic acid, vinylacetate, acrylates and acrolein; b. placing the monomer solution containing the at least one compound in a pressure vessel, pressurizing the pressure vessel and removing oxygen from the pressure vessel; and c. heating the monomer solution containing the at least one compound, wherein the at least one compound inhibits fouling by preventing polymerization of the monomer.

An apparatus comprises a first controller configured to control at least the flow rate of a polymerization inhibitor or acrylonitrile product to a first location where the two are mixed. The apparatus comprises a first on-line analyzer configured to measure polymerization inhibitor concentration in the acrylonitrile product at a second location, the second location downstream of the first location. The first on-line analyzer is configured to provide information relating to the measured inhibitor concentration at the second location to the first controller, the first controller configured to process the information from the first on-line analyzer and to adjust at least a first operating parameter of a first addition device if the measured inhibitor concentration at the second location is outside a first predetermined condition. A second controller and a second on-line analyzer are provided to provide similar control of water addition to acrylonitrile product.

An apparatus comprises a first controller configured to control at least the flow rate of a polymerization inhibitor or acrylonitrile product to a first location where the two are mixed. The apparatus comprises a first on-line analyzer configured to measure polymerization inhibitor concentration in the acrylonitrile product at a second location, the second location downstream of the first location. The first on-line analyzer is configured to provide information relating to the measured inhibitor concentration at the second location to the first controller, the first controller configured to process the information from the first on-line analyzer and to adjust at least a first operating parameter of a first addition device if the measured inhibitor concentration at the second location is outside a first predetermined condition. A second controller and a second on-line analyzer are provided to provide similar control of water addition to acrylonitrile product.

An apparatus comprises a first controller configured to control at least the flow rate of a polymerization inhibitor or acrylonitrile product to a first location where the two are mixed. The apparatus comprises a first on-line analyzer configured to measure polymerization inhibitor concentration in the acrylonitrile product at a second location, the second location downstream of the first location. The first on-line analyzer is configured to provide information relating to the measured inhibitor concentration at the second location to the first controller, the first controller configured to process the information from the first on-line analyzer and to adjust at least a first operating parameter of a first addition device if the measured inhibitor concentration at the second location is outside a first predetermined condition. A second controller and a second on-line analyzer are provided to provide similar control of water addition to acrylonitrile product.

The present invention relates to a novel process for preparation of 2-Cyano-3,3-diarylacrylates by the Knoevenagel condensation of Cyanoacetic esters and Arylketones using ammonium compound and acetic acid and without the use of organic solvent.

The present invention relates to a novel process for preparation of 2-Cyano-3,3-diarylacrylates by the Knoevenagel condensation of Cyanoacetic esters and Arylketones using ammonium compound and acetic acid and without the use of organic solvent.

The present invention relates to a novel process for preparation of 2-Cyano-3,3-diarylacrylates by the Knoevenagel condensation of Cyanoacetic esters and Arylketones using ammonium compound and acetic acid and without the use of organic solvent.