An aqueous acid composition that may be used, for example, in a matrix acidizing treatment can include an acid, a polymeric acid corrosion inhibitor, and an acid corrosion inhibitor intensifier. The acid corrosion inhibitor can include iodide ions and metal ions, with the metal ions being one or more of copper, silver, bismuth, or antimony. The molar ratio of metal ions to iodide ions can be 1:X, where X is greater than or equal to 2. The polymer of the polymeric acid corrosion inhibitor can have a molecular weight less than 100,000 g/mol.

A method for inhibiting corrosion of pipelines and other metal surfaces, particularly those used in the oil-and-gas industry, is disclosed. The method comprises treating a brine-exposed metal surface with a film-forming composition. The composition comprises a quaternary surfactant, which is made by reacting a polyalkylene glycol (PAG), a haloalkanoic acid, and a tertiary fatty amine that optionally incorporates amide or ester functionality. The surfactant comprises a PAG monoester quat and a PAG diester diquat and may have other components. The quaternary surfactants provide good corrosion protection and can partition effectively from an oily phase into a brine phase in the absence of agitation. The surfactants are easy to synthesize economically and have structures that can be tailored to meet local HLB requirements.

A method for inhibiting corrosion of pipelines and other metal surfaces, particularly those used in the oil-and-gas industry, is disclosed. The method comprises treating a brine-exposed metal surface with a film-forming composition. The composition comprises a quaternary surfactant, which is made by reacting a polyalkylene glycol (PAG), a haloalkanoic acid, and a tertiary fatty amine that optionally incorporates amide or ester functionality. The surfactant comprises a PAG monoester quat and a PAG diester diquat and may have other components. The quaternary surfactants provide good corrosion protection and can partition effectively from an oily phase into a brine phase in the absence of agitation. The surfactants are easy to synthesize economically and have structures that can be tailored to meet local HLB requirements.

Compounds, compositions and methods are provided for reducing, inhibiting, or preventing corrosion of a surface, using a corrosion-inhibiting composition comprising a dispersant having the structure of Formula 1 and a corrosion inhibitor having the structure of Formula 2

##STR00001##

wherein X.sub.1 is hydroxyl, —OC(O)R.sub.1; X.sub.2 is hydroxyl, or —OC(O)R.sub.2; X.sub.3 is hydroxyl or —OC(O)R.sub.3; R.sub.1, R.sub.2, and R.sub.3 are independently C.sub.10 to C.sub.30 alkyl or alkenyl; m, n, and o are independently integers from 1 to 10; R.sub.20 , R.sub.21, R.sub.22, R.sub.23, and R.sub.24 are independently hydrogen or —C(O)—R.sub.31; R.sub.31 is C.sub.10 to C.sub.30 alkyl or alkenyl; p is an integer of 0 or 1; q is an integer of 1 to 4; r is an integer of 0 or 1; s is an integer of 0 or 1; t is an integer from 1 to 4; and p1, q1, r1, r2, s1, and t1 are independently integers from 1 to 6; wherein when p, r, and s are 0, q+t is an integer from 4 to 8 and at least one of R.sub.20 , R.sub.21, R.sub.22, R.sub.23, and R.sub.24 is —C(O)—R.sub.31.

The present disclosure relates to biocide compositions, formulations and methods for using formulations. In particular the present disclosure relates to biocide compositions and their use in effecting biocidal activity in subterranean oil and gas wells being drilled, completed, worked over or produced.

The present disclosure relates to biocide compositions, formulations and methods for using formulations. In particular the present disclosure relates to biocide compositions and their use in effecting biocidal activity in subterranean oil and gas wells being drilled, completed, worked over or produced.

A method is disclosed that includes introducing a scavenger composition into a fluid stream contaminated with a sulfur contaminant such that the scavenger composition reacts with the sulfur contaminant to reduce an amount of the sulfur contaminant in the fluid stream, wherein the scavenger composition includes a hydrogen sulfide scavenger and an anionic linear polymer. A composition is disclosed that includes a hydrogen sulfide scavenger; and an anionic linear polymer.

A method is disclosed that includes introducing a scavenger composition into a fluid stream contaminated with a sulfur contaminant such that the scavenger composition reacts with the sulfur contaminant to reduce an amount of the sulfur contaminant in the fluid stream, wherein the scavenger composition includes a hydrogen sulfide scavenger and an anionic linear polymer. A composition is disclosed that includes a hydrogen sulfide scavenger; and an anionic linear polymer.

A method of inhibiting corrosion of metal during acid stimulation of an oil and gas well, whereby the oil and gas well is treated with an acidic treatment fluid containing 10 to 28 wt. % of an acid and 0.001 to 0.045 wt. % of a corrosion inhibitor of formula I, each based on a total weight of the acidic treatment fluid,

##STR00001##

wherein R.sup.1 to R.sup.5 are independently hydrogen, an optionally substituted alkyl, an optionally substituted aryl, an optionally substituted alkoxy, an optionally substituted alkanoyloxy, a carboxy, an optionally substituted alkoxycarbonyl, a hydroxy, a halo, a nitro, a cyano, or wherein two of these adjacent substituents represented by R.sup.1 to R.sup.5, together form a methylene dioxy group.

A method of inhibiting corrosion of metal during acid stimulation of an oil and gas well, whereby the oil and gas well is treated with an acidic treatment fluid containing 10 to 28 wt. % of an acid and 0.001 to 0.045 wt. % of a corrosion inhibitor of formula I, each based on a total weight of the acidic treatment fluid,

##STR00001##

wherein R.sup.1 to R.sup.5 are independently hydrogen, an optionally substituted alkyl, an optionally substituted aryl, an optionally substituted alkoxy, an optionally substituted alkanoyloxy, a carboxy, an optionally substituted alkoxycarbonyl, a hydroxy, a halo, a nitro, a cyano, or wherein two of these adjacent substituents represented by R.sup.1 to R.sup.5, together form a methylene dioxy group.