Radical initiators and chain extenders for converting methane gas into methane-sulfonic acid
View Patent ↗Improved initiators, solvents, and SO3 mixtures are disclosed herein, which can increase the yields and efficiency of a chemical manufacturing process which uses a radical chain reaction to convert methane (CH4), which is a gas under any normal conditions, into methane-sulfonic acid (MSA), a liquid. MSA is useful and valuable in its own right, and it also can be processed to create desulfured fuels and other valuable chemicals. A preferred initiator combination has been identified, comprising at least two different sulfate peroxide compounds. One type or class of initiator can be called a “primary” (or major, main, principle, dominant, or similar terms) initiator, and the other type or class of initiator can be can be regarded as an “extender” (or secondary, supplemental, enhancing, tuning, tweaking, or similar terms) initiator. “Primary” initiator(s) include (unmethylated) Marshall's acid, mono-methyl-Marshall's acid, and di-methyl-Marshall's acid, while a secondary/extender initiator comprises methyl-Caro's acid, which can oxidize sulfur DI-oxide (an unwanted chain terminator) into sulfur TRI-oxide (an essential reagent). Various other enhancements to the MSA manufacturing process also are described.
1. A chemical mixture for initiating a radical chain reaction which will convert methane into methane-sulfonic acid, comprising:
(i) at least one primary initiator compound having a peroxide bond which when broken apart will release radical species capable of efficiently removing hydrogen atoms from methane, being selected from the group consisting of Marshall's acid (peroxy-di-sulfuric-acid), methyl-Marshall's acid (methyl-sulfonyl-peroxo-sulfuric acid), and dimethyl-Marshall's acid (dimethyl-sulfonyl-peroxide); and,
(ii) methyl-Caro's acid (methyl-sulfonyl-peroxy-acid) as an extender initiator having a peroxide bond which when broken apart will release at least one radical species that will oxidize SO2 (sulfur dioxide) molecules into SO3 (sulfur trioxide) molecules, wherein the quantity of said extender initiator is not more than 10% of the total initiator weight thereby removing chain-terminating sulfur dioxide molecules from the radical chain reaction.
2. The chemical mixture of claim 1 , further comprising a mixture of sulfuric acid and methane-sulfonic acid as a liquid solvent.
3. The chemical mixture of claim 1 , further comprising methane-sulfonic acid as a liquid solvent.
4. A method for performing a radical chain reaction, comprising the steps of introducing, into a reactor vessel, a mixture comprising:
(i) at least one primary initiator compound having a peroxide bond which when broken apart will release radical species capable of efficiently removing hydrogen atoms from at least one hydrocarbon or carbohydrate reagent, wherein said primary initiator compound is selected from the group consisting of Marshall's acid (peroxy-di-sulfuric-acid), methyl-Marshall's acid (methyl-sulfonyl-peroxo-sulfuric acid), and dimethyl-Marshall's acid (dimethyl-sulfonyl-peroxide, DMSP), and combinations thereof; and,
(ii) methyl-Caro's acid (methyl-sulfonyl-peroxy-acid) as an extender initiator having a peroxide bond which, when broken apart, will release at least one radical species that will oxidize sulfur dioxide molecules into sulfur trioxide molecules wherein the quantity of said extender initiator is not more than 10% of the total initiator weight.
5. The chemical mixture of claim 1 wherein said primary initiator compound is created by subjecting to electrolysis a combination of sulfuric acid and methane-sulfonic acid.
6. The mixture of claim 1 for converting methane into methane-sulfonic acid via a radical chain reaction, wherein ozone is utilized to react with a reagent selected from the group consisting of sulfur trioxide (SO 3 ) and methane sulfonic acid (MSA) to thereby produce a sulfur-containing peroxide compound which when broken apart will release radicals that will remove hydrogen atoms from methane molecules, thereby creating methyl radicals.
7. The method of claim 4 wherein the reactor vessel comprises a tube enclosure which contains at least one internal inert baffle-type mixing device, wherein said tube enclosure can process a gas/liquid mixture at a pressure in the range of from at least 500 pounds/square inch up to 1500 pounds/square inch, under plug flow conditions.
8. The reactor vessel of claim 7 wherein said tube enclosure comprises multiple linear segments of tubing, coupled together to create a continuous flow path through multiple tubing segments.
9. The method of claim 4 wherein (i) said extender initiator is injected separately into the reactor vessel but continuously while said primary initiator is introduced into the reactor vessel or (ii) said extender initiator is injected intermittently into the reactor vessel while said primary initiator is introduced into the reactor vessel.
10. The method of claim 4 wherein the extender initiator is generated within the reactor vessel.