Abstract: Disclosed are compositions and methods for preventing or reducing polymer formation and polymer deposition in equipment used in petrochemical processes. An antifoulant composition includes a combination of one or more antioxidants; one or more antipolymerants; one or more dispersants; and one or more solvents. A method of preventing or reducing fouling of process equipment used in an industrial process is also described. The method includes introducing into the process equipment an antifoulant composition, the antifoulant composition comprising a combination of one or more antioxidants; one or more antipolymerants; one or more dispersants; and one or more solvents.

Abstract: Described are compositions and methods for inhibiting polymerization of a monomer (e.g., styrene) composition, which use an N—O polymerization inhibitor, a quinone methide polymerization retarder, and an amine stabilizer having a primary and/or secondary amine group. In a mixture, the amine-based stabilizer can prevent antagonistic effects and can provide greater antipolymerant activity. In turn, the mixture inhibits apparatus fouling and improves the purity of monomer streams.

Abstract: Disclosed herein are methods for reducing fouling caused by process water present within a water recycling loop of a pyrolysis plant. Fouling is caused by phase separation and accumulation of materials from the process water on equipment surfaces. The method includes applying a total of about 5 ppm to 500 ppm total of a first polymerization inhibitor and second polymerization inhibitor to the process water to form a treated process water, wherein the first polymerization inhibitor has a pygas-water partition coefficient of about 0.0001 to 9 and the second polymerization inhibitor has a pygas-water partition coefficient of about 1000 to 50,000.

Abstract: Disclosed are compositions and methods for preventing or reducing polymer formation and polymer deposition in equipment used in petrochemical processes. An antifoulant composition includes a combination of one or more antioxidants; one or more antipolymerants; one or more dispersants; and one or more solvents. A method of preventing or reducing fouling of process equipment used in an industrial process is also described. The method includes introducing into the process equipment an antifoulant composition, the antifoulant composition comprising a combination of one or more antioxidants; one or more antipolymerants; one or more dispersants; and one or more solvents.

Abstract: Disclosed are compositions and methods for preventing or reducing polymer formation and polymer deposition in equipment used in petrochemical processes. An antifoulant composition includes a combination of one or more antioxidants; one or more antipolymerants; one or more dispersants; and one or more solvents. A method of preventing or reducing fouling of process equipment used in an industrial process is also described. The method includes introducing into the process equipment an antifoulant composition, the antifoulant composition comprising a combination of one or more antioxidants; one or more antipolymerants; one or more dispersants; and one or more solvents.

Abstract: Described are compositions and methods for inhibiting polymerization of a monomer (e.g., styrene) composition, which use an N—O polymerization inhibitor, a quinone methide polymerization retarder, and an amine stabilizer having a primary and/or secondary amine group. In a mixture, the amine-based stabilizer can prevent antagonistic effects and can provide greater antipolymerant activity. In turn, the mixture inhibits apparatus fouling and improves the purity of monomer streams.

Abstract: Disclosed herein are compositions including between 20 wt % and 50 wt % of a nitroxyl compound such as 2,2,6,6-tetramethylpiperidinyl-1-oxyl. The compositions are stable under field conditions of transportation and storage. The compositions remain homogeneous and pumpable or pourable at temperatures between ?20° C. and 60° C., even when temperatures fluctuate in this range over a period of 10 days to 5 years, and even where the container used to transport and store the composition is made from metal or includes a metal surface contacting the composition.

Abstract: Disclosed herein are methods for reducing fouling caused by process water present within a water recycling loop of a pyrolysis plant. Fouling is caused by phase separation and accumulation of materials from the process water on equipment surfaces. The method includes applying a total of about 5 ppm to 500 ppm total of a first polymerization inhibitor and second polymerization inhibitor to the process water to form a treated process water, wherein the first polymerization inhibitor has a pygas-water partition coefficient of about 0.0001 to 9 and the second polymerization inhibitor has a pygas-water partition coefficient of about 1000 to 50,000.

Abstract: Disclosed herein are compositions including between 20 wt % and 50 wt % of a nitroxyl compound such as 2,2,6,6-tetramethylpiperidinyl-1-oxyl. The compositions are stable under field conditions of transportation and storage. The compositions remain homogeneous and pumpable or pourable at temperatures between ?20° C. and 60° C., even when temperatures fluctuate in this range over a period of 10 days to 5 years, and even where the container used to transport and store the composition is made from metal or includes a metal surface contacting the composition.

Abstract: Disclosed are compositions and methods for preventing or reducing polymer formation and polymer deposition in equipment used in petrochemical processes. An antifoulant composition includes a combination of one or more antioxidants; one or more antipolymerants; one or more dispersants; and one or more solvents. A method of preventing or reducing fouling of process equipment used in an industrial process is also described. The method includes introducing into the process equipment an antifoulant composition, the antifoulant composition comprising a combination of one or more antioxidants; one or more antipolymerants; one or more dispersants; and one or more solvents.

Abstract: The present invention generally relates to compounds and methods for inhibiting the radical polymerization of unsaturated compounds, particularly vinyl monomers. More particularly, it relates to the use of stable hydroxyl amines to inhibit the polymerization of unsaturated compounds (e.g., vinyl monomers) wherein said stable hydroxylamine is soluble in organic solvents, particularly hydrocarbon solvents consisting of unsaturated and, therefore, polymerizable constituents.

Abstract: Disclosed herein are systems and methods for monitoring and controlling a nitroxide-based polymerization inhibitor in vinyl-based monomers. A dosage of the nitroxide-based polymerization inhibitor is provided in the vinyl-based monomers. A residual concentration of the nitroxide-based polymerization inhibitor is measured substantially in real time, and an optimized dosage of the nitroxide-based polymerization inhibitor is provided in response to the measured residual concentration.

Abstract: The present invention generally relates to compounds and methods for inhibiting the radical polymerization of unsaturated compounds, particularly vinyl monomers. More particularly, it relates to the use of stable hydroxyl amines to inhibit the polymerization of unsaturated compounds (e.g., vinyl monomers) wherein said stable hydroxylamine is soluble in organic solvents, particularly hydrocarbon solvents consisting of unsaturated and, therefore, polymerizable constituents.

Abstract: Disclosed herein are systems and methods for monitoring and controlling a nitroxide-based polymerization inhibitor in vinyl-based monomers. A dosage of the nitroxide-based polymerization inhibitor is provided in the vinyl-based monomers. A residual concentration of the nitroxide-based polymerization inhibitor is measured substantially in real time, and an optimized dosage of the nitroxide-based polymerization inhibitor is provided in response to the measured residual concentration.

Abstract: Disclosed herein are systems and methods for monitoring and controlling a nitroxide-based polymerization inhibitor in vinyl-based monomers. A dosage of the nitroxide-based polymerization inhibitor is provided in the vinyl-based monomers. A residual concentration of the nitroxide-based polymerization inhibitor is measured substantially in real time, and an optimized dosage of the nitroxide-based polymerization inhibitor is provided in response to the measured residual concentration.

Abstract: Disclosed herein are systems and methods for monitoring and controlling a nitroxide-based polymerization inhibitor in vinyl-based monomers. A dosage of the nitroxide-based polymerization inhibitor is provided in the vinyl-based monomers. A residual concentration of the nitroxide-based polymerization inhibitor is measured substantially in real time, and an optimized dosage of the nitroxide-based polymerization inhibitor is provided in response to the measured residual concentration.