Inhibited hydrofluoric acid composition

1. An inhibited hydrofluoric acid aqueous composition, said composition comprising:

hydrofluoric acid in solution; and

a weak base selected from the group consisting of: lysine, arginine, histidine, glutamine, asparagine, tryptophan, and tyrosine;

wherein said weak base and hydrofluoric acid are present in a molar ratio of at least 1.1:1.

2. The composition of claim 1 , wherein the weak base is lysine.

3. A method of etching a glass, the method comprising:

providing a glass surface for etching;

providing an inhibited hydrofluoric acid aqueous composition according to claim 1 ;

combining said inhibited hydrofluoric acid aqueous composition with an acid composition sufficient to dissociate an amount of HF required to etch glass;

applying the combination of inhibited hydrofluoric acid aqueous composition and acid composition to said glass surface for a sufficient time period to etch said glass surface.

4. The method of claim 3 , wherein the acid composition is selected from the group consisting of acids having a pKa value of less than 3.

5. The method of claim 4 , wherein the acid having a pKa value of less than 3 is methanesulfonic acid.

6. The method of claim 4 , wherein the acid having a pKa value of less than 3 is sulfamic acid.

7. The method of claim 4 , wherein the acid having a pKa value of less than 3 is selected from the group consisting of: hydrochloric acid, nitric acid, sulfuric acid, modified acids, and organic acids.

8. The method of claim 7 , wherein the modified acid is selected from the group consisting of: MEA-HCl, urea-HCl, and lysine-HCl.

9. A mud acid composition comprising:

an inhibited hydrofluoric acid aqueous composition according to claim 1 ; and:

an acid having a pKa value of less than 3.

10. The mud acid composition of claim 9 , where the acid with a pKa of less than 3 is selected from the group consisting of: HCl, MEA-HCl, urea-HCl, methanesulfonic acid, sulfuric acid, sulfamic acid, and lysine-HCl.

11. The mud acid composition of claim 9 , wherein the weak base is lysine.

12. A method of using a mud acid to acidize a sandstone formation, said method comprises the steps of:

providing an inhibited hydrofluoric acid composition according to claim 1 ;

providing an acid composition, said acid composition adapted to activate the inhibited hydrofluoric acid composition when put in contact therewith;

combining the inhibited hydrofluoric acid composition with said acid composition to create a mud acid; and

applying said mud acid to a silicate-containing formation and allowing said mud acid composition sufficient exposure time to dissolve a pre-determined amount of silica.

13. The method of claim 12 , wherein the inhibited hydrofluoric acid composition is provided by injecting it directly into the acid composition.

14. The method of claim 12 , wherein the addition of the inhibited hydrofluoric acid composition is done by injecting it directly into the flowing acid composition by a venturi entrainment of the inhibited hydrofluoric acid by the acid composition.

15. A method for removing silica or silicate deposits on a metal surface, said method comprising the steps of:

providing an inhibited hydrofluoric acid composition, according to claim 1 ;

providing an acid composition, said acid composition comprising a corrosion inhibitor package and adapted to activate the inhibited hydrofluoric acid composition when put in contact therewith;

combining the inhibited hydrofluoric acid composition with said acid composition to create a mud acid; and

applying said mud acid to the metal surface.

16. The method of claim 15 , wherein the corrosion inhibitor package comprises:

a metal iodide;

a terpene;

a cinnamaldehyde or a derivative thereof;

at least one amphoteric surfactant;

a solvent; and

optionally, a non-emulsifier.

17. The method of claim 16 , wherein the metal iodide is potassium iodide.

18. The method of claim 15 , wherein the corrosion inhibitor package comprises:

a metal iodide;

a terpene;

a cinnamaldehyde or derivative thereof;

at least one amphoteric surfactant;

a solvent; and

a non-emulsifier.