Complete removal of solids during hydrogen sulfide scavenging operations using a scavenger and a Michael acceptor
Disclosed herein are scavenging and antifouling compositions useful in applications relating to the production, transportation, storage, and separation of crude oil and natural gas. Also disclosed herein are methods of using the compositions as scavengers and antifoulants, particularly in applications relating to the production, transportation, storage, and separation of crude oil and natural gas.
1. A composition, comprising:
a Michael acceptor,
a scavenging compound, and
an anaerobic polymerization inhibitor,
wherein the scavenging compound comprises formaldehyde and/or a formaldehyde equivalent, and wherein the Michael acceptor comprises an α,β-unsaturated ester.
2. The composition of claim 1 , wherein the Michael acceptor comprises the following structure:
wherein R is selected from H, methyl, or ethyl and n is a number from 1 to 10.
3. The composition of claim 1 , wherein the α,β-unsaturated ester is selected from the group consisting of an ethoxylated ester, a propoxylated ester, an acrylate ester, and any combination thereof.
4. The composition of claim 1 , wherein the α,β-unsaturated ester is selected from the group consisting of a mono-ethoxylate of acrylic acid, a di-ethoxylate of acrylic acid, a tri-ethoxylate of acrylic acid, a mono-propoxylate of acrylic acid, a di-propoxylate of acrylic acid, a tri-propoxylate of acrylic acid, and any combination thereof.
5. The composition of claim 1 , wherein the α,β-unsaturated ester is selected from the group consisting of methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, propyl hydroxyl ester, hydroxyl butyl acrylate, hydroxyl ethyl acrylate, and any combination thereof.
6. The composition of claim 1 , wherein the formaldehyde equivalent comprises an alkyl hemiformal compound and/or an alkanol hemiformal compound.
7. The composition of claim 1 , wherein the formaldehyde equivalent comprises the following structure:
wherein R 1 , R 2 , and R 3 are each independently selected from the group consisting of hydrogen, alkylenyl, alkenylenyl, alkynylenyl, alkyl, alkenyl, and alkynyl, wherein said alkylenyl, alkenylenyl, alkynylenyl, alkyl, alkenyl, and alkynyl are each independently, at each occurrence, substituted or unsubstituted with one or more suitable substituents;
k, l, and m are each independently an integer selected from the group consisting of 0 to 25, wherein k+l+m is >0; and
x, y, and z are each independently an integer selected from the group consisting of 0 and 1, wherein x+y+z is 1, 2, or 3;
provided that:
when x is 0, R 1 is hydrogen, alkyl, alkenyl, or alkynyl; and when x is 1, R 1 is alkylenyl, alkenylenyl, or alkynylenyl;
when y is 0, R 2 is hydrogen, alkyl, alkenyl, or alkynyl; and when y is 1, R 2 is alkylenyl, alkenylenyl, or alkynylenyl;
when z is 0, R 3 is hydrogen, alkyl, alkenyl, or alkynyl; and when z is 1, R 3 is alkylenyl, alkenylenyl, or alkynylenyl; and
when x is 1, y is 1, z is 1, k is 1, l is 1, and m is 1, then R 1 , R 2 , and R 3 are not simultaneously unsubstituted C 2 -alkylenyl.
8. The composition of claim 7 , wherein x+y+z is 3, and R 1 , R 2 , and R 3 are each selected from the group consisting of alkylenyl, C 2 -alkylenyl, unsubstituted C 2 -alkylenyl, and any combination thereof.
9. The composition of claim 7 , wherein x is 1, y is 1, z is 0, R 1 and R 2 are each alkylenyl, and R 3 is alkyl.
10. The composition of claim 7 , wherein x is 1, y is 1, z is 0, R 1 and R 2 are each alkylenyl, and R 3 is hydrogen.
11. The composition of claim 7 , wherein the formaldehyde equivalent comprises the following formula (II),
wherein
R 3 is selected from the group consisting of hydrogen, alkylenyl, alkenylenyl, alkynylenyl, alkyl, alkenyl, and alkynyl, wherein said alkylenyl, alkenylenyl, alkynylenyl, alkyl, alkenyl, and alkynyl are each independently substituted or unsubstituted with one or more suitable substituents;
k, l, and m are each independently an integer selected from the group consisting of 0 to 25, wherein k+l+m is >0; and
z is 0 or 1;
provided that:
when z is 1, R 3 is alkylenyl, alkenylenyl, or alkynylenyl;
when z is 0, R 3 is hydrogen, alkyl, alkenyl, or alkynyl; and
when z is 1, k is 1, l is 1, and m is 1, then R 3 is not an unsubstituted C 2 -alkylenyl
12. The composition of claim 1 , wherein the anaerobic polymerization inhibitor comprises a member selected from the group consisting of 4-hydroxy-2,2,6,6-tetramethyl piperidinoxyl
(HTMPO), phenothiazine, and any combination thereof.
13. The composition of claim 1 , wherein the composition comprises from about 1 to about 35 weight % of the Michael acceptor and about 1 to about 80 weight % of the formaldehyde and/or formaldehyde equivalent.
14. The composition of claim 1 , wherein the composition comprises from about 1 to about 35 weight % of the Michael acceptor, from about 1 to about 80 weight % of the formaldehyde or formaldehyde equivalent, and from about 10 ppm to about 10,000 ppm of the anaerobic polymerization inhibitor.
15. The composition of claim 1 , further comprising from about 1 to about 20 weight % of triethanolamine.
16. The composition of claim 1 , wherein the composition comprises the formaldehyde equivalent and further comprises a glycol ether solvent, triethanolamine, and hydroxyl ethyl acrylate, wherein the formaldehyde equivalent is an alkanol hemiformal.
17. The composition of claim 1 , wherein the composition comprises the formaldehyde and further comprises water and optionally methanol.
18. The composition of claim 1 , wherein the composition is anhydrous.
19. A method of scavenging hydrogen sulfide, comprising:
adding the composition of claim 1 to a fluid or gas comprising the hydrogen sulfide and allowing the composition to react with the hydrogen sulfide, thereby scavenging the hydrogen sulfide.