A method of passivating a metal surface of hydrocarbon processing equipment is provided in which a water soluble molybdate compound is introduced into water or steam which is in contact or will come into contact with a metal surface of the hydrocarbon processing equipment to passivate the metal surface to inhibit surface coke formation.

A method of passivating a metal surface of hydrocarbon processing equipment is provided in which a water soluble molybdate compound is introduced into water or steam which is in contact or will come into contact with a metal surface of the hydrocarbon processing equipment to passivate the metal surface to inhibit surface coke formation.

A method of inhibiting asphaltene precipitation and/or deposition in a hydrocarbon, preferably crude oil, by adding to the hydrocarbon a polyester asphaltene dispersing agent which is the reaction product of an alk(en)yl substituted succinic anhydride wherein the average number of succinic groups per alk(en)yl group is less than 2.0, and at least one polyol.

A process for preparing a drag reducing polymer which is to be added to a liquid hydrocarbon. The liquid hydrocarbon has an asphaltene content of at least about 3 weight percent and an API gravity of less than about 26°. The drag reducing polymer can comprise the residues of a monomer having at least one heteroatom. Treatment of the liquid hydrocarbon with the drag reducing polymer allows a reduction in pressure drop associated with turbulent flow of the liquid hydrocarbon through a conduit.

A process for preparing a drag reducing polymer which is to be added to a liquid hydrocarbon. The liquid hydrocarbon has an asphaltene content of at least about 3 weight percent and an API gravity of less than about 26°. The drag reducing polymer can comprise the residues of a monomer having at least one heteroatom. Treatment of the liquid hydrocarbon with the drag reducing polymer allows a reduction in pressure drop associated with turbulent flow of the liquid hydrocarbon through a conduit.

Sulfide stress cracking of a metal component may be inhibited by treating the metal component with a mixture comprising at least one organic aldehyde and at least one surfactant. Such metal components may be those suitable for use in a downhole environment, at a well site, in a storage facility, in a transportation infrastructure, in a refinery facility, and any combination thereof where the metal component may be exposed to hydrogen sulfide.

Sulfide stress cracking of a metal component may be inhibited by treating the metal component with a mixture comprising at least one organic aldehyde and at least one surfactant. Such metal components may be those suitable for use in a downhole environment, at a well site, in a storage facility, in a transportation infrastructure, in a refinery facility, and any combination thereof where the metal component may be exposed to hydrogen sulfide.

The present invention relates to an additive composition for controlling and inhibiting polymerization of monomers, wherein the composition comprises a combination of (a) a phenol compound comprising catechol compound with (b1) an aliphatic tertiary amine, (b2) oxide treated derivative of the aliphatic tertiary amine, or (b2) a mixture thereof, wherein the aliphatic tertiary amine contains one or more hydroxyl groups in the alkyl chain of the aliphatic tertiary amine. In one embodiment, the present invention also relates to a method for controlling and inhibiting polymerization of monomers by employing the additive composition of the present invention. In another embodiment, the present invention also relates to a method of using the additive composition of the present invention for controlling and inhibiting polymerization of monomers. In another embodiment, the present invention also relates to methods for controlling and inhibiting polymerization of monomers in a primary fractionator (or an ethylene plant), and for operating a primary fractionator, and for reducing fouling and polymer deposits in a primary fractionator, and to extend a run-length of a primary fractionator or of an ethylene plant.

The present invention relates to an additive composition for controlling and inhibiting polymerization of monomers, wherein the composition comprises a combination of (a) a phenol compound comprising catechol compound with (b1) an aliphatic tertiary amine, (b2) oxide treated derivative of the aliphatic tertiary amine, or (b2) a mixture thereof, wherein the aliphatic tertiary amine contains one or more hydroxyl groups in the alkyl chain of the aliphatic tertiary amine. In one embodiment, the present invention also relates to a method for controlling and inhibiting polymerization of monomers by employing the additive composition of the present invention. In another embodiment, the present invention also relates to a method of using the additive composition of the present invention for controlling and inhibiting polymerization of monomers. In another embodiment, the present invention also relates to methods for controlling and inhibiting polymerization of monomers in a primary fractionator (or an ethylene plant), and for operating a primary fractionator, and for reducing fouling and polymer deposits in a primary fractionator, and to extend a run-length of a primary fractionator or of an ethylene plant.

Compositions may include those of the formula: (I) wherein R1 is an alkyl chain having a carbon number in the range of greater than 40 to 200, R2 is a multiester, R3 is hydrogen, an ion, or an alkyl chain having a carbon number in the range of 1 to 200, m is an integer selected from 0 to 4, and n is an integer selected from the range of 0 to 4, wherein the sum of m and n is 1 or greater. Compositions may include a reaction product of a polyisobutylene-substituted succinic anhydride and a hydroxy-functional dendrimer, wherein the molar ratio of polyisobutylene-substituted succinic anhydride to hydroxy-functional dendrimer is within the range of 10:1 to 30:1.

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