A cleaning liquid and an anticorrosion agent having an excellent corrosion inhibition function, and a method for manufacturing the same. The cleaning liquid contains alkanol hydroxyamine represented by general formula (1), alkanolamine represented by general formula (2), a solvent, and a basic compound other than the alkanol hydroxyamine and the alkanolamine or an acidic compound. In the general formula (1), R.sup.a1 and R.sup.a2 each independently represents a C1-C10 alkyl group having one to three hydroxy groups, or a hydrogen atom, R.sup.a1 and R.sup.a2 are not simultaneously a hydrogen atom, and R.sup.b1 and R.sup.b2 are not simultaneously a hydrogen atom. ##STR00001##

An aqueous modified acid composition for industrial activities, said composition comprising: an alkanolamine and strong acid in a molar ratio of not less than 1:15, preferably not less than 1:10; it can also further comprise a metal iodide or iodate. Said composition demonstrates advantages over known conventional acids and modified acids.

Compositions and methods are provided for reducing, inhibiting, or preventing corrosion of a surface, the method comprising contacting an anticorrosion compound of Formula 1 with the surface, the anticorrosion compound of Formula 1 having a structure corresponding to: ##STR00001##
wherein R.sup.1, R.sup.2, R.sup.3, R.sup.4, and R.sup.5 are independently selected from hydrogen, hydroxyl, alkyl, alkoxyl, aryl, alkaryl, aralkyl, and NR.sup.8R.sup.9; R.sup.6 and R.sup.7 are independently hydrogen, a substituted alkyl, substituted alkenyl, substituted aryl, substituted alkaryl, or substituted aralkyl, wherein at least one substituent is a hydroxyl or an ether; provided that at least one of R.sup.6 and R.sup.7 is other than hydrogen; R.sup.8 and R.sup.9 are independently hydrogen, unsubstituted alkyl, unsubstituted alkenyl, unsubstituted aryl, unsubstituted alkaryl, unsubstituted aralkyl, substituted alkyl, substituted alkenyl, or substituted alkaryl, wherein at least one substituent is a hydroxyl or an ether; or any two adjacent groups of R.sup.1, R.sup.2, R.sup.3, R.sup.4, and R.sup.5 form one or more ring structures.

An aqueous modified acid composition for industrial activities, said composition comprising: an alkanolamine and strong acid in a molar ratio of not less than 1:15, preferably not less than 1:10; it can also further comprise a metal iodide or iodate. Said composition demonstrates advantages over known conventional acids and modified acids.

An aqueous modified acid composition for industrial activities, said composition comprising: an alkanolamine and strong acid in a molar ratio of not less than 1:15, preferably not less than 1:10; it can also further comprise a metal iodide or iodate. Said composition demonstrates advantages over known conventional acids and modified acids.

A corrosion inhibition composition includes a carrier fluid and corrosion inhibitor consisting essentially of a compound represented by Formula (I):

##STR00001## where R.sub.1, R.sub.2, R.sub.3, and R.sub.4 are each, independently, a hydrogen or an alkoxy group, and m and n are each, independently integers ranging from 2 to 10, where R.sub.5 and R.sub.6 are each, independently, a saturated C.sub.6-C.sub.10 hydrocarbon group or an unsaturated C.sub.6-C.sub.10 hydrocarbon group. A method of producing a corrosion inhibition composition consisting essentially of an ethoxylated diamine corrosion inhibitor and a carrier fluid and a method for inhibiting corrosion in a refined hydrocarbon-bearing system are also described.

The present invention provides a deoxidizing agent for boilers excellent in an oxygen removal effect under wide temperature conditions. The deoxidizing agent for boilers comprises (A) a hydroxylamine compound represented by the following general formula (I), (B) a heterocyclic compound having an N-substituted amino group, and (C) an aminophenol derivative represented by the following general formula (II),

##STR00001## wherein R.sup.1 and R.sup.2 each independently represent an alkyl group having 1 to 5 carbon atoms;

##STR00002## wherein R.sup.3 to R.sup.6 each independently represent any one of (a) the following general formula (III), (b) OR.sup.10 and (c) R.sup.11, at least one of R.sup.3 to R.sup.6 representing (a), and R.sup.10 and R.sup.11 each independently represent a hydrogen atom or an alkyl group having 1 to 4 carbon atoms;

##STR00003## wherein R.sup.7 represents a single bond or an alkylene group having 1 to 4 carbon atoms, and R.sup.8 and R.sup.9 each independently represent a hydrogen atom or an alkyl group having 1 to 4 carbon atoms.

Compounds comprising multiple hydrophilic heads and a lipophilic tail may be contacted with a metal or other surface so as to adhere to the surface and inhibit corrosion, among other things. Suitable hydrophilic heads may include quaternary ammonium cation moieties, phosphonium cation moieties, and combinations thereof. Such corrosion-inhibiting compounds may be introduced into a wellbore penetrating at least a portion of a subterranean formation, for instance in oil and/or gas recovery operations and the like, whereupon the compound may adhere to a metal or other surface downhole so as to inhibit corrosion of the surface. These compounds may be employed in various other environments, such as any metal or other surface that may be exposed to corrosive conditions.

Compositions and methods are provided for reducing, inhibiting, or preventing corrosion of a surface, the method comprising contacting an anticorrosion compound of Formula 1 with the surface, the anticorrosion compound of Formula 1 having a structure corresponding to:

##STR00001##

wherein R.sup.1, R.sup.2, R.sup.3, R.sup.4, and R.sup.5 are independently selected from hydrogen, hydroxyl, alkyl, alkoxyl, aryl, alkaryl, aralkyl, and NR.sup.8R.sup.9; R.sup.6 and R.sup.7 are independently hydrogen, a substituted alkyl, substituted alkenyl, substituted aryl, substituted alkaryl, or substituted aralkyl, wherein at least one substituent is a hydroxyl or an ether; provided that at least one of R.sup.6 and R.sup.7 is other than hydrogen; R.sup.8 and R.sup.9 are independently hydrogen, unsubstituted alkyl, unsubstituted alkenyl, unsubstituted aryl, unsubstituted alkaryl, unsubstituted aralkyl, substituted alkyl, substituted alkenyl, or substituted alkaryl, wherein at least one substituent is a hydroxyl or an ether; or any two adjacent groups of R.sup.1, R.sup.2, R.sup.3, R.sup.4, and R.sup.5 form one or more ring structures.

An aqueous modified acid composition for industrial activities, said composition comprising: an alkanolamine and strong acid in a molar ratio of not less than 1:15, preferably not less than 1:10; it can also further comprise a metal iodide or iodate. Said composition demonstrates advantages over known conventional acids and modified acids.