ACIDIC AQUEOUS SOLUTION CONTAINING CHELATING AGENT AND USE THEREOF Russian patent published in 2013 - IPC C09K8/74 C09K8/528 E21B43/27 C11D7/32 

FIELD: chemistry.

SUBSTANCE: invention relates to an acidic aqueous solution containing a chelating agent and an acid, wherein the chelating agent is glutamic N,N-diacetic acid (GLDA) or a salt thereof and wherein the amount of GLDA or the salt thereof is 20-60 wt %, based on the weight of the aqueous solution, and wherein the acid is selected from hydrochloric acid, hydrobromic acid, hydrofluoric acid, hydroiodic acid, sulphuric acid, nitric acid, phosphoric acid, formic acid, acetic acid, citric acid, lactic acid, malic acid, tartaric acid, maleic acid, boric acid, hydrogen sulphide or a mixture of two or more of these acids, and use of said solution in cleaning processes, precipitation processes or processes of removing salt deposits, at oil fields in completion and stimulation by acid treatment, fracturing and/or deposit removal. The acidic aqueous solution has pH below 3.

EFFECT: obtaining a solution with a higher acidic pH and higher content of biodegradable highly soluble chelating agent.

4 cl, 2 dwg