Flow reactor vessels and reactor systems

1. A process for forming a thiol compound, the process comprising:

(i) introducing a fluid comprising H 2 S and a compound having a carbon-carbon double bond into a flow reactor vessel, the flow reactor vessel comprising:

(a) a reaction chamber comprising a reactor wall, an inlet for the fluid, and an outlet;

(b) a tube positioned within the reaction chamber, and a flow path for the fluid including a region between an outer surface of the tube and an inner surface of the reactor wall; and

(c) an electromagnetic radiation source enclosed within the tube, the electromagnetic radiation source configured to deliver electromagnetic radiation into the fluid in the flow path;

wherein an average linear distance between the outer surface of the tube and the inner surface of the reactor wall is less than or equal to 10 cm;

(ii) exposing the fluid to the electromagnetic radiation within the reaction chamber to form the thiol compound; and

(iii) discharging a composition comprising the thiol compound from the reaction chamber via the outlet;

wherein the fluid in the flow path has a volumetric flow rate from 12 to 120 gallons/min and a Reynolds number from 10,000 to 250,000; and

wherein step (ii) is conducted at a reaction pressure sufficient to maintain H 2 S in the liquid phase.

2. The process of claim 1 , wherein the fluid in step (i) comprises a molar ratio of H 2 S to carbon-carbon double bonds of the compound having a carbon-carbon double bond in a range from 5:1 to 500:1.

3. The process of claim 1 , wherein the fluid in step (i) further comprises a phosphite compound at a molar ratio of the phosphite compound to carbon-carbon double bonds of the compound having a carbon-carbon double bond in a range from 0.006:1 to 0.05:1.

4. The process of claim 1 , wherein the fluid in step (i) further comprises a photoinitiator at a weight percentage in a range from 0.05 to 5 wt. %, based on the weight of the compound having a carbon-carbon double bond.

5. The process of claim 1 , wherein:

the electromagnetic radiation is ultraviolet light;

and

step (ii) is conducted at a reaction pressure in a range from 1.72 to 13.79 MPa.

6. The process of claim 1 , wherein the compound having a carbon-carbon double bond has from 1 to 10 double bonds.

7. The process of claim 1 , wherein the compound having a carbon-carbon double bond comprises ethylene, propylene, 1-butene, 2-butene, 3-methyl-1-butene, isobutylene, 1-pentene, 2-pentene, 3-methyl-1-pentene, 4-methyl-1-pentene, 1-hexene, 2-hexene, 3-ethyl-1-hexene, 1-heptene, 2-heptene, 3-heptene, 1-octene, 1-decene, 1-dodecene, styrene, or any combination thereof.

8. The process of claim 1 , wherein the compound having a carbon-carbon double bond comprises an unsaturated triglyceride, an unsaturated natural source oil, or both.

9. The process of claim 1 , wherein the average linear distance between the outer surface of the tube and the inner surface of the reactor wall is greater than 10 times the electromagnetic radiation penetration depth into the fluid in the flow path.

10. The process of claim 1 , wherein the fluid is substantially free of an organic reaction medium.

11. The process of claim 1 , wherein the tube is a quartz tube having a wall thickness from 3.5 mm to 10 mm.

12. A process for forming a thiol compound, the process comprising:

(i) introducing a fluid comprising H 2 S and a compound having a carbon-carbon double bond into a flow reactor vessel, the flow reactor vessel comprising:

(a) a reaction chamber comprising a reactor wall, an inlet for the fluid, and an outlet;

(b) a tube positioned within the reaction chamber, and a flow path for the fluid including a region between an outer surface of the tube and an inner surface of the reactor wall; and

(c) an electromagnetic radiation source enclosed within the tube, the electromagnetic radiation source configured to deliver electromagnetic radiation into the fluid in the flow path;

wherein an average linear distance between the outer surface of the tube and the inner surface of the reactor wall is less than or equal to 10 cm;

(ii) exposing the fluid to the electromagnetic radiation within the reaction chamber to form the thiol compound; and

(iii) discharging a composition comprising the thiol compound from the reaction chamber via the outlet;

wherein the fluid in the flow path has a volumetric flow rate from 12 to 120 gallons/min and a Reynolds number of at least 10,000.

13. The process of claim 12 , wherein the fluid in the flow path has a Reynolds number of at least 25,000.

14. The process of claim 12 , wherein the fluid in the flow path has a Reynolds number of at least 50,000.

15. The process of claim 12 , wherein:

the electromagnetic radiation is ultraviolet light; and

the fluid makes more than one pass through the flow reactor vessel.

16. The process of claim 12 , wherein:

the Reynolds number is from 25,000 to 200,000;

the electromagnetic radiation is ultraviolet light; and

the compound having a carbon-carbon double bond has from 2 to 6 double bonds.

17. The process of claim 12 , wherein the fluid in step (i) comprises a molar ratio of H 2 S to carbon-carbon double bonds of the compound having a carbon-carbon double bond in a range from 15:1 to 150:1.

18. The process of claim 12 , wherein step (ii) is conducted at a reaction pressure in a range from 1.72 MPa to 13.79 MPa.

19. The process of claim 12 , wherein the tube is a quartz tube having a wall thickness from 3.5 mm to 10 mm.

20. The process of claim 12 , wherein the fluid in step (i) further comprises:

a phosphite compound at a molar ratio of the phosphite compound to carbon-carbon double bonds of the compound having a carbon-carbon double bond in a range from 0.006:1 to 0.05:1; and/or

a photoinitiator at a weight percentage in a range from 0.05 to 5 wt. %, based on the weight of the compound having a carbon-carbon double bond.