Drilling fluid composition containing treated date pit particles and methods of use thereof

1. A drilling fluid composition, comprising:

a viscosifier;

treated date pit particles, which are

i) de-oiled and

ii) treated with a base or both a base and an acid; and

an aqueous base fluid;

wherein the treated date pit particles are present in an amount of 0.01-5 wt %, relative to a total weight of the drilling fluid composition.

2. The drilling fluid composition of claim 1 , wherein the viscosifier is bentonite.

3. The drilling fluid composition of claim 1 , wherein the viscosifier is present in an amount of 1-10 wt %, relative to a total weight of the drilling fluid composition.

4. The drilling fluid composition of claim 1 , wherein the treated date pit particles are ii) treated with a base.

5. The drilling fluid composition of claim 4 , wherein the base is sodium hydroxide.

6. The drilling fluid composition of claim 4 , which has a filtration water loss volume of 15-28 mL after 30 min under a pressure of 100 psi.

7. The drilling fluid composition of claim 1 , wherein the treated date pit particles are ii) treated with both a base and an acid.

8. The drilling fluid composition of claim 7 , wherein the base is sodium hydroxide and the acid is acetic acid or sulfuric acid.

9. The drilling fluid composition of claim 7 , which has a filtration water loss volume of 30-40 mL after 30 min under a pressure of 100 psi.

10. The drilling fluid composition of claim 1 , which has a density of 6.5-8.5 lb/gal.

11. The drilling fluid composition of claim 1 , which has a plastic viscosity of 3.0-3.5 cP.

12. The drilling fluid composition of claim 1 , further comprising at least one additive selected from the group consisting of an antiscalant, a thickener, a deflocculant, a lubricant, a buffer, a biocide, and a weighting agent.

13. The drilling fluid composition of claim 1 , which is substantially free of a fluid loss additive, a density reducing agent, and a rheology modifying agent, other than the treated date pit particles and the viscosifier.

14. A method of making the drilling fluid composition of claim 1 , comprising:

contacting dried date pit particles with an organic solvent to remove oils and form de-oiled date pit particles;

mixing the de-oiled date pit particles with a base and water to form an alkaline mixture;

subjecting the alkaline mixture to a freeze/thaw process and optionally adding an acid to form a freeze/thaw mixture comprising the treated date pit particles in water; and

adding the freeze/thaw mixture to the viscosifier and the aqueous base fluid to form the drilling fluid composition.

15. The method of claim 14 , wherein the organic solvent is at least one selected from the group consisting of pentane, hexane, methanol, and ethanol.

16. The method of claim 14 , wherein the base is sodium hydroxide and the acid, when added, is acetic acid or sulfuric acid.

17. The method of claim 14 , wherein the freeze/thaw process comprises

subjecting the alkaline mixture to a temperature of −20° C. or below for at least 4 hours to form a frozen mixture,

thawing the frozen mixture at a temperature of 20-50° C.; and

agitating for at least 15 minutes to form the freeze/thaw mixture.

18. A process for drilling a subterranean geological formation, comprising:

drilling the subterranean geological formation with a drill bit to form a wellbore; and

injecting the drilling fluid composition of claim 1 into the subterranean geological formation through the wellbore.

19. The process of claim 18 , wherein the treated date pit particles are ii) treated with a base, and the drilling fluid composition is injected into the subterranean geological formation through the wellbore to maintain a pressure in the wellbore that is higher than a static pressure of the subterranean geological formation.

20. The process of claim 18 , wherein the treated date pit particles are ii) treated with both a base and an acid, and the drilling fluid composition is injected into the subterranean geological formation through the wellbore to maintain a pressure in the wellbore that is lower than a static pressure of the subterranean geological formation.