Disclosed is a conversion composition containing a trivalent chromium cation in an amount of 0.001 g/L to 20 g/L. Also disclosed is a system for treating a metal substrate that includes the conversion composition and a sealing composition comprising a lithium cation. Also disclosed is a method for treating a metal substrate that includes contacting at least a portion of a surface of the substrate with the conversion composition and then contacting at least a portion of the surface of the substrate with the sealing composition. Also disclosed is a substrate obtainable by treatment with the system and/or obtainable by the method of treating.

Methods for cleaning a superalloy substrate having engine deposits on its surface are provided. The method may include applying a permanganate solution onto the surface of the superalloy substrate, and applying a ferric chloride based cleaning composition onto the surface of the superalloy substrate. The ferric chloride based cleaning composition includes ferric chloride and at least one of nitric acid and phosphoric acid, such as within a solvent system (e.g., an aqueous solution including water).

A stripper composition and a cleaning method are provided. The stripper composition includes an amine-based compound (A), a fatty acid (B) and a solvent (C). Based on a total usage amount of 100 wt % of the stripper composition, a usage amount of water is 1 wt % or less.

A stripper composition and a cleaning method are provided. The stripper composition includes an amine-based compound (A), a fatty acid (B) and a solvent (C). Based on a total usage amount of 100 wt % of the stripper composition, a usage amount of water is 1 wt % or less.

The invention relates to a method for removing a substrate that is coated with an organic coated coating by means of ionogenic gel formation. In said method, a wet or dry organic coating that has not yet formed a film on the substrate is treated with an aqueous solution of a metal salt from main group I in the periodic table of the elements, a complexing agent and/or a basic compound having a pH value >10.

The invention relates to a method for removing a substrate that is coated with an organic coated coating by means of ionogenic gel formation. In said method, a wet or dry organic coating that has not yet formed a film on the substrate is treated with an aqueous solution of a metal salt from main group I in the periodic table of the elements, a complexing agent and/or a basic compound having a pH value >10.

Disclosed herein is a borate-free, aqueous cleaning and treating composition including at least one metasilicate (A); at least one orthophosphate (B); at least one phosphate (C); at least one surfactant (D); and where the aqueous cleaning and treating composition has a pH value at 20 C. in a range from 11.0 to 12.8; and possesses a molar ratio of Si atoms to P atoms being from 0.75:1 to 1:0.75, based on the sum of the Si-containing metasilicates (A) and the sum of the P-containing orthophosphates (B), diphosphates (C) and triphosphates (C). Further disclosed herein are solid mixtures. Additionally disclosed herein are a method for cleaning and treating metallic substrates by using the compositions and a method of using the compositions to clean metallic substrates and treat metallic substrates by forming a Si-containing layer on the surface of the metallic substrates.

Disclosed herein is a borate-free, aqueous cleaning and treating composition including at least one metasilicate (A); at least one orthophosphate (B); at least one phosphate (C); at least one surfactant (D); and where the aqueous cleaning and treating composition has a pH value at 20 C. in a range from 11.0 to 12.8; and possesses a molar ratio of Si atoms to P atoms being from 0.75:1 to 1:0.75, based on the sum of the Si-containing metasilicates (A) and the sum of the P-containing orthophosphates (B), diphosphates (C) and triphosphates (C). Further disclosed herein are solid mixtures. Additionally disclosed herein are a method for cleaning and treating metallic substrates by using the compositions and a method of using the compositions to clean metallic substrates and treat metallic substrates by forming a Si-containing layer on the surface of the metallic substrates.

A system for descaling heat exchanger surfaces using a varying concentration of either an acidic or alkaline solution, selecting an optimum pH value for descaling a heat exchanger according to the level of cleaning the heat exchanger requires, monitoring pH value of descaling solution during circulation through a heat exchanger, and adding chemical solution to achieve coincidence of optimum and monitored pH values during descaling operation.

A system for descaling heat exchanger surfaces using a varying concentration of either an acidic or alkaline solution, selecting an optimum pH value for descaling a heat exchanger according to the level of cleaning the heat exchanger requires, monitoring pH value of descaling solution during circulation through a heat exchanger, and adding chemical solution to achieve coincidence of optimum and monitored pH values during descaling operation.