A process for chemical cleaning and corrosion inhibition of pipework, typically in closed loop systems, that avoids or significantly minimises the requirement for wastewater discharge where the system is first acidified using a mixture of cleaning agents capable of dissolving metal oxides. The method then precipitates any dissolved contaminants and separates the precipitate from the carrying fluid. Further elements of a combined corrosion inhibitor package are then added to any cleaning agent ions that remain in solution to develop a fully functional corrosion inhibition package to protect the metals of the system.

A composition for inhibiting corrosion and/or removing hydrocarbonaceous deposits in oil and gas applications is provided. The composition comprises an iron sulfide dissolver, an organic solvent, and a corrosion inhibitor.

A heterocyclic compound having a structure in which a benzene ring and a nitrogen-containing heterocycle are condensed is added to a sulfuric acid solution that contains a persulfuric acid component such as peroxomonosulfuric acid, peroxomonosulfate, peroxodisulfuric acid, or peroxodisulfate as an oxidant and in which impurities that promote the reduction in the oxidant concentration are present. Here, the heterocyclic compound having a structure in which a benzene ring and a nitrogen-containing heterocycle are condensed is preferably a benzotriazole-based compound. The impurities that promote a reduction in the oxidant concentration are suitably one or more selected from copper ions, iron ions, nitrate ions, and nitrite ions. The method of the present invention of inhibiting a reduction in the oxidant concentration in a sulfuric acid solution containing a persulfuric acid component can inhibit the reduction in the oxidant concentration to a minimum even when impurities that cause a reduction in the oxidant concentration are mixed.

A method includes additively manufacturing an article in an inert environment, removing the article from the inert environment and placing the article in a non-inert environment, allowing at least a portion the article to oxidize in the non-inert environment to form an oxidized layer on a surface of the article, and removing the oxidized layer (e.g., to smooth the surface of the article). The method can further include relieving stress in the article (e.g., via heating the article after additive manufacturing).

A composition for inhibiting corrosion and/or removing hydrocarbonaceous deposits in oil and gas applications is provided. The composition comprises an iron sulfide dissolver, an organic solvent, and a corrosion inhibitor.

This invention provides a liquid composition that removes titanium nitride from a substrate without corroding tungsten or a low-k interlayer dielectric also present on said substrate. Said liquid composition has a pH between 0 and 4, inclusive, and contains the following: at least one oxidizing agent (A) selected from the group consisting of potassium permanganate, ammonium peroxodisulfate, potassium peroxodisulfate, and sodium peroxodisulfate; a fluorine compound (B); and a tungsten-corrosion preventer (C). The tungsten-corrosion preventer (C) either contains at least two different compounds selected from a group of compounds (C1) consisting of alkylamines, salts thereof, fluoroalkylamines, salts thereof, and the like or contains at least one compound selected from said group of compounds (C1) and at least one compound selected from a group of compounds (C2) consisting of polyoxyalkylene alkylamines, polyoxyalkylene fluoroalkylamines, and the like. The mass concentration of potassium permanganate in the abovementioned oxidizing agent (A) is between 0.001% and 0.1%, inclusive, and the mass concentration of the abovementioned fluorine compound (B) is between 0.01% and 1%, inclusive.

A cleaning solution for a turbine engine includes water; a first organic acidic component that comprises citric acid; a second organic acidic component that comprises glycolic acid; isopropylamine sulphonate; alcohol ethoxylate; triethanol amine; and sodium lauriminodipropionate. The cleaning solution has a pH value between about 2.5 and about 7.0.

An aqueous composition for reducing corrosive removal of material in pickling of metallic surfaces comprising bare and/or galvanized steel. The composition includes a mixture of a compound of the formula R.sup.1O—(CH.sub.2).sub.x—C≡C—(CH.sub.2).sub.y—OR.sup.2 in which R.sup.1 and R.sup.2 are both H, and a compound of the formula R.sup.1O—(CH.sub.2).sub.x—C≡C—(CH.sub.2).sub.y—OR.sup.2 in which R.sup.1 and R.sup.2 are each, independently of one another, an HO—(CH.sub.2).sub.w— group with w≥2. X and y are each, independently of one another, from 1 to 4 in each of the two compounds of the formula R.sup.1O—(CH.sub.2).sub.x—C≡C—(CH.sub.2).sub.y—OR.sup.2. A process for pickling a metallic surface with reduced corrosive removal of material is disclosed.

Disclosed is a cleaning agent for a metal member that may include an amount of about 15 wt % to 30 wt % of an organic acid derived from a monosaccharide, or a salt thereof, an amount of about 0.8 wt % to 1.2 wt % of a chelating agent, an amount of about 0.2 wt % to 0.4 wt % of a surfactant and an amount of about 75 wt % to 85 wt % of a solvent, based on the total weight of the cleaning agent. The acid cleaning agent may be prepared using, as a main material, an organic acid mixture including potassium glucarate, thus exhibiting superior acid cleaning capability and minimizing the generation of offensive odors. The cleaning agent of the present invention may be eco-friendly because the working environment using the same is made comfortable.

The present disclosure relates to a corrosion inhibitor formulation comprising: a) at least one quaternary ammonium salt; b) at least one fatty acid methyl ester; c) at least one viscosity reducing agent; and d) at least one solubilizing agent, wherein the at least one quaternary ammonium salt to the at least one fatty acid methyl ester weight ratio is in the range of 1:0.2-1:5.0. The instant disclosure further relates to the process of preparation of the corrosion inhibitor formulation.