US-12624297-B1 - Removal of hydrogen sulfide and/or mercaptans from oil or oil derivatives and treatment compositions for accomplishing the same

Abstract

Aqueous treatment compositions for crude oil and/or petroleum distillates to remove sulfur compounds therefrom and treatment methods using such compositions are disclosed. The composition has less than 0.5% wt/wt di- or tri-benzohydroxy compound, a strong base, less than 1% wt/wt divalent metal gluconate, a balance of water, and a pH that is 9 or greater. The treatment method includes adding said treatment composition to crude oil or a petroleum distillate to form a mixture having 0.001% to 0.02% wt di- or tri-benzohydroxy compound/wt oil and 0.001% to 0.03% wt divalent metal gluconate/wt oil and mixing the same together.

Inventors

• Linda Esther Schweitzer
• Bobby Burkes, SR.

Assignees

• Ripcord Energy Solutions, LLC

Dates

Publication Date

20260512

Application Date

20240409

Claims (18)

1. 1 . A treatment composition for crude oil and/or petroleum distillates comprising: about 0.05% to about 1% wt/wt di- or tri-benzohydroxy compound; a mixture of sodium hydroxide and/or potassium hydroxide; about 0.1% to about 1% wt/wt divalent metal gluconate or metallic zinc powder; and balance water; wherein the treatment composition has a pH of 11 or greater.
2. 2 . The treatment composition of claim 1 , wherein the di- or tri-benzohydroxy compound comprises hydroquinone and/or pyrogallol.
3. 3 . The treatment composition of claim 2 , wherein the di- or tri-benzohydroxy compound comprises a mixture of hydroquinone and pyrogallol.
4. 4 . The treatment composition of claim 3 , wherein the pyrogallol has percent wt/wt concentration greater than the percent wt/wt of the hydroquinone.
5. 5 . The treatment composition of claim 4 , wherein the percent wt/wt of the pyrogallol is at least 500 times greater than the percent wt/wt of the hydroquinone.
6. 6 . The treatment composition of claim 1 , wherein the treatment composition comprises about 0.05% to about 0.5% wt/wt di- or tri-benzohydroxy compound.
7. 7 . The treatment composition of claim 1 , wherein the treatment composition comprises the divalent metal gluconate.
8. 8 . The treatment composition of claim 7 , wherein the divalent metal gluconate is selected from the group consisting of zinc gluconate, magnesium gluconate, calcium gluconate, iron (II) gluconate, copper (II) gluconate and combinations thereof.
9. 9 . The treatment composition of claim 7 , wherein the divalent metal gluconate is present as about 0.1% to about 0.8% wt/wt.
10. 10 . The treatment composition of claim 7 , wherein the divalent metal gluconate is present as about 0.1% to about 0.6% wt/wt.
11. 11 . The treatment composition of claim 7 , wherein the divalent metal gluconate comprises zinc gluconate and/or magnesium gluconate.
12. 12 . The treatment composition of claim 11 , wherein the divalent metal gluconate comprises a mixture of zinc gluconate and magnesium gluconate.
13. 13 . The treatment composition of claim 12 , wherein the zinc gluconate has a percent wt/wt concentration that is greater than the percent wt/wt of magnesium gluconate.
14. 14 . The treatment composition of claim 13 , wherein the percent wt/wt of zinc gluconate is about 10 times greater than the percent wt/wt of magnesium gluconate.
15. 15 . The treatment composition of claim 1 , wherein the pH is equal to or greater than the second pKa of hydrogen sulfide.
16. 16 . The treatment composition of claim 1 , wherein the treatment composition comprises a mixture of sodium hydroxide and potassium hydroxide.
17. 17 . The treatment composition of claim 16 , wherein the mixture of sodium hydroxide and potassium hydroxide is present as about a 1:1 ratio by percent weight.
18. 18 . The treatment composition of claim 1 , wherein the treatment composition comprises about 0.05% to about 0.2% wt/wt di- or tri-benzohydroxy compound.

Description

RELATED APPLICATIONS This application is a continuation of U.S. application Ser. No. 18/355,592, filed Jul. 20, 2023, which claims the benefit of U.S. Provisional Application 63/369,088, filed Jul. 22, 2022, the entirety of which is incorporated herein by reference. TECHNICAL FIELD The present application relates the removal of hydrogen sulfide and/or mercaptans from oil, more particularly, from crude oil and/or petroleum distillates by an oxidation reaction caused by treatment with a caustic solution of a divalent metal gluconate and a di- or tri-benzohydroxy compound. BACKGROUND Removal of hydrogen sulfide from oils has been a long-standing problem as evidenced by U.S. Pat. No. 2,468,701 filed Jan. 25, 1945, which is still an unresolved need as evidenced by U.S. Pat. Nos. 4,206,194; 5,180,572; and 6,746,611. Along with hydrogen sulfide, it is desirable to remove mercaptans as well. Both are volatile toxic gases often present in crude oil. Crude oil that has a high sulfur content can lead to corrosion, catalyst poisoning, and environmental pollution. If the sulfur content remains, it can be present in gasoline, diesel fuel, and jet fuel, which is undesirable. Numerous sulfur compounds can be present in the crude oil. Here is a list of sulfur compounds in order of increasing difficulty of removal from crude oil: disulfides (R—S—S—R); sulfides (R—S—R); thiols (R—CHCH3)—CH2—SH); thiophenol (Phe-SH); diphenyl sulfide (Phe-S-Phe); thiophen (C4H4S) or dibenzothiophene (C12H8S). A common treatment process for crude oil is caustic washing. Caustic washing removes sulfides from crude oil and petroleum distillates. While this method is relatively simple and cost effective, it does not remove all sulfur forms therefrom, especially organic sulfides and it results in large quantity of caustic soda (NaOH/KOH) wastewater that is an environmental hazard. The wastewater is typically collected in large ponds for post-treatment. Such post-treatments are costly and time consuming. Furthermore, the oil will be imparted with sodium, and residual alkalinity, which can make the oil corrosive and can cause scaling problems in pipelines and other infrastructure. Moreover, at high pH, the presence of sulfide ions can cause reactions with metals. Caustic washing can also cause a water-in-oil emulsion and foam from saponification of fatty acids in the oil. Others have tried dry gas desulfurization, hydrodesulfurization, and bio-desulfurization, which are much more expensive methods. Triazine and other amines are commonly used liquid scavengers that strip hydrogen sulfide out of oil, but residual triazine in oil can cause fouling and corrosion of pipes, towers, and other equipment. While these methods have been shown to reduce hydrogen sulfide in oil, there is always a need to find a more cost effective, more environmentally friendly process that is also faster and more effective at removing sulfur compounds from crude oil and petroleum distillates, including removal of mercaptans, not just hydrogen sulfide. SUMMARY In a first aspect, methods of treating crude oil or petroleum distillates are disclosed. The methods include providing a crude oil or petroleum distillate in need of a reduced content of sulfur containing compounds and adding a treatment composition thereto. The treatment composition has a pH of 9 or greater and comprises: (a) less than 1% wt/wt di- or tri-benzohydroxy compound;(b) a strong base;(c) less than 0.5% wt/wt divalent metal gluconate; and(d) a balance of water. The method also includes mixing the treatment composition and the crude oil or petroleum distillate to form a mixture comprising 0.001% to 0.02% wt (a)/wt oil and 0.001% to 0.03% wt (c)/wt oil. Upon mixing (a) in the presence of (c) oxidizes a sulfur compound in the crude oil or petroleum distillate, thereby reducing the amount thereof in the crude oil or petroleum distillate. During the adding and mixing oxygen gas can be introduced. The oxygen gas source can be ambient air. The method can optionally include adding 1000 ppm or less of a 30% wt/wt hydrogen peroxide aqueous solution after mixing the treatment composition with the crude oil or petroleum distillate and washing the mixture with toluene, ozonated water, or a hydrogen peroxide solution after the reduction in the amount of sulfur compounds present. Alternately, the method can include adding 1000 ppm or less of polyethylene glycol after mixing the treatment composition with the crude oil or petroleum distillate. Typically, the sulfur compound is hydrogen sulfide and/or a mercaptan. In one embodiment, (a) is present as less than 0.2% wt/wt of the treatment composition and (a) is hydroquinone and/or pyrogallol, more preferably hydroquinone and pyrogallol. The wt/wt concentration of pyrogallol is greater than the wt/wt concentration of hydroquinone. In one embodiment, the pH is at least 13. In one embodiment, (c) comprises zinc gluconate and/or magnesium gluconate, more preferably a mixture of zinc