Deionisation and clarification process of the aqueous medium used in an electroerosion machine and product for this process, where the electroerosion machines are comprised of a purification circuit for this aqueous medium, which includes an ion exchange phase between some cationic and anionic resins with the aqueous dielectric medium, which has a conductivity of less than 40 .mu.S/cm, and to which a solution of oxalic acid and phosphoric acid in distilled/deionised water is added in the approximate proportion of oxalic acid between 0.18 and 0.035 moles and phosphoric acid between 1.28 and 2.5 moles per liter of solution.

The present invention provides a composition that is suitable for lowering the alkalinity of a textile. The composition is also suitable for cleansing or treating a hard surface or a porous surface. The composition exhibits stability as a solution or as a dispersion at a temperature of about 0.degree. C. to about 8.degree. C. The composition includes a carrier, an acid, and a quaternary phosphonium compound, or a suitable salt or solvate thereof. The present invention also provides a method for cleansing or treating a surface. The method includes contacting the surface with an effective amount of a composition of the present invention to provide a treated or cleansed surface having a pH below about 7.5. The present invention also provides a method for preparing a composition of the present invention. The method includes combining the carrier, the acid, and the quaternary phosphonium compound, or a suitable salt or solvate thereof, in any order, to provide the composition.