CN118355003A - Process for the preparation of tetrahydrothiophenes - Google Patents
Process for the preparation of tetrahydrothiophenes Download PDFInfo
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- CN118355003A CN118355003A CN202280080367.1A CN202280080367A CN118355003A CN 118355003 A CN118355003 A CN 118355003A CN 202280080367 A CN202280080367 A CN 202280080367A CN 118355003 A CN118355003 A CN 118355003A
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- China
- Prior art keywords
- catalyst
- stage
- process according
- tetrahydrothiophene
- weight
- Prior art date
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- RAOIDOHSFRTOEL-UHFFFAOYSA-N tetrahydrothiophene Chemical class C1CCSC1 RAOIDOHSFRTOEL-UHFFFAOYSA-N 0.000 title claims abstract description 35
- 238000000034 method Methods 0.000 title claims description 21
- 238000002360 preparation method Methods 0.000 title description 5
- WERYXYBDKMZEQL-UHFFFAOYSA-N butane-1,4-diol Chemical compound OCCCCO WERYXYBDKMZEQL-UHFFFAOYSA-N 0.000 claims abstract description 41
- WYURNTSHIVDZCO-UHFFFAOYSA-N Tetrahydrofuran Chemical compound C1CCOC1 WYURNTSHIVDZCO-UHFFFAOYSA-N 0.000 claims abstract description 36
- 239000003054 catalyst Substances 0.000 claims abstract description 34
- 239000007789 gas Substances 0.000 claims abstract description 22
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 claims abstract description 17
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 claims abstract description 16
- RWSOTUBLDIXVET-UHFFFAOYSA-N Dihydrogen sulfide Chemical compound S RWSOTUBLDIXVET-UHFFFAOYSA-N 0.000 claims abstract description 13
- YLQBMQCUIZJEEH-UHFFFAOYSA-N tetrahydrofuran Natural products C=1C=COC=1 YLQBMQCUIZJEEH-UHFFFAOYSA-N 0.000 claims abstract description 12
- 229910002092 carbon dioxide Inorganic materials 0.000 claims abstract description 9
- 238000004519 manufacturing process Methods 0.000 claims abstract description 9
- KKCBUQHMOMHUOY-UHFFFAOYSA-N sodium oxide Chemical compound [O-2].[Na+].[Na+] KKCBUQHMOMHUOY-UHFFFAOYSA-N 0.000 claims abstract description 9
- 229910001948 sodium oxide Inorganic materials 0.000 claims abstract description 9
- 239000001569 carbon dioxide Substances 0.000 claims abstract description 7
- 238000006243 chemical reaction Methods 0.000 claims description 21
- 239000012071 phase Substances 0.000 claims description 7
- 239000012074 organic phase Substances 0.000 claims description 5
- 239000008346 aqueous phase Substances 0.000 claims description 3
- 238000010908 decantation Methods 0.000 claims description 3
- 229910000272 alkali metal oxide Inorganic materials 0.000 claims description 2
- 229910000287 alkaline earth metal oxide Inorganic materials 0.000 claims description 2
- 229910052799 carbon Inorganic materials 0.000 abstract description 3
- 230000003197 catalytic effect Effects 0.000 description 12
- 239000000376 reactant Substances 0.000 description 6
- 229910000831 Steel Inorganic materials 0.000 description 4
- 229910000037 hydrogen sulfide Inorganic materials 0.000 description 4
- 239000011734 sodium Substances 0.000 description 4
- 239000010959 steel Substances 0.000 description 4
- 230000015572 biosynthetic process Effects 0.000 description 3
- 238000003786 synthesis reaction Methods 0.000 description 3
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 2
- -1 CO 2 Substances 0.000 description 2
- YTPLMLYBLZKORZ-UHFFFAOYSA-N Thiophene Chemical compound C=1C=CSC=1 YTPLMLYBLZKORZ-UHFFFAOYSA-N 0.000 description 2
- 239000002253 acid Substances 0.000 description 2
- 239000000047 product Substances 0.000 description 2
- VXNZUUAINFGPBY-UHFFFAOYSA-N 1-Butene Chemical compound CCC=C VXNZUUAINFGPBY-UHFFFAOYSA-N 0.000 description 1
- OXBLVCZKDOZZOJ-UHFFFAOYSA-N 2,3-Dihydrothiophene Chemical compound C1CC=CS1 OXBLVCZKDOZZOJ-UHFFFAOYSA-N 0.000 description 1
- VGGSQFUCUMXWEO-UHFFFAOYSA-N Ethene Chemical compound C=C VGGSQFUCUMXWEO-UHFFFAOYSA-N 0.000 description 1
- 239000005977 Ethylene Substances 0.000 description 1
- 238000003916 acid precipitation Methods 0.000 description 1
- 239000000654 additive Substances 0.000 description 1
- 230000000996 additive effect Effects 0.000 description 1
- IAQRGUVFOMOMEM-UHFFFAOYSA-N butene Natural products CC=CC IAQRGUVFOMOMEM-UHFFFAOYSA-N 0.000 description 1
- 239000006227 byproduct Substances 0.000 description 1
- 230000000052 comparative effect Effects 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 239000007857 degradation product Substances 0.000 description 1
- 238000004821 distillation Methods 0.000 description 1
- 230000014509 gene expression Effects 0.000 description 1
- 239000002638 heterogeneous catalyst Substances 0.000 description 1
- 238000011065 in-situ storage Methods 0.000 description 1
- 239000011261 inert gas Substances 0.000 description 1
- 238000002347 injection Methods 0.000 description 1
- 239000007924 injection Substances 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 229910052757 nitrogen Inorganic materials 0.000 description 1
- QQONPFPTGQHPMA-UHFFFAOYSA-N propylene Natural products CC=C QQONPFPTGQHPMA-UHFFFAOYSA-N 0.000 description 1
- 125000004805 propylene group Chemical group [H]C([H])([H])C([H])([*:1])C([H])([H])[*:2] 0.000 description 1
- 238000000746 purification Methods 0.000 description 1
- 238000007086 side reaction Methods 0.000 description 1
- 238000003860 storage Methods 0.000 description 1
- XTQHKBHJIVJGKJ-UHFFFAOYSA-N sulfur monoxide Chemical class S=O XTQHKBHJIVJGKJ-UHFFFAOYSA-N 0.000 description 1
- 229910052815 sulfur oxide Inorganic materials 0.000 description 1
- 238000004381 surface treatment Methods 0.000 description 1
- 229930192474 thiophene Natural products 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07D—HETEROCYCLIC COMPOUNDS
- C07D333/00—Heterocyclic compounds containing five-membered rings having one sulfur atom as the only ring hetero atom
- C07D333/02—Heterocyclic compounds containing five-membered rings having one sulfur atom as the only ring hetero atom not condensed with other rings
- C07D333/04—Heterocyclic compounds containing five-membered rings having one sulfur atom as the only ring hetero atom not condensed with other rings not substituted on the ring sulphur atom
- C07D333/06—Heterocyclic compounds containing five-membered rings having one sulfur atom as the only ring hetero atom not condensed with other rings not substituted on the ring sulphur atom with only hydrogen atoms, hydrocarbon or substituted hydrocarbon radicals, directly attached to the ring carbon atoms
- C07D333/08—Hydrogen atoms or radicals containing only hydrogen and carbon atoms
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
- Heterocyclic Carbon Compounds Containing A Hetero Ring Having Oxygen Or Sulfur (AREA)
- Low-Molecular Organic Synthesis Reactions Using Catalysts (AREA)
Abstract
The invention relates to a process for preparing tetrahydrothiophene, comprising the stage of reacting 1, 4-butanediol or tetrahydrofuran in the gas phase in the presence of alumina as catalyst, having a sodium oxide content of less than 0.3% by weight relative to the total weight of the catalyst, at a temperature between 200 ℃ and 320 ℃, in the presence of hydrogen sulfide (H 2 S) and optionally carbon dioxide.
Description
The present invention relates to a process for the production of tetrahydrothiophene with improved yields.
Tetrahydrothiophenes are compounds which show great industrial interest. It is known as an additive in consumable gases for detecting possible leaks, since it is very characteristic of smell. As a result, it is present in the gas injected into the home supply network, in the gas transport network, in the storage unit and in the interconnections with other gas transport networks.
Tetrahydrothiophene (hereinafter referred to as THT) is synthesized in the presence of a heterogeneous catalyst from: 1, 4-butanediol (hereinafter referred to as BDO) or tetrahydrofuran (hereinafter referred to as THF) are known.
It is accepted in the literature that the first in situ stage is the conversion of BDO to THF according to the following reaction:
1,4-BDO→THF+H2O
The second stage is the conversion of THF to THT in the presence of H 2 S according to the following reaction:
THF+H2S→THT+H2O
in fact, the following side reactions can occur depending on the operating conditions:
THT→Dihydrothiophene+H 2
THT→thiophene+2H 2
THT+H 2 - & gt propylene +CH 3 SH
THT+H 2 →butene+H 2 S
In addition, the synthesis may produce degradation products such as CO 2, ethylene, and C 1 to C 4 mercaptans.
In fact, from the current ecological point of view, there is now a real need for a more efficient process for the synthesis of tetrahydrothiophenes, that is to say in higher yields and secondly in lower proportions of the product.
This is because these reaction secondary products or byproducts are difficult to recycle. They are generally incinerated and result in high emissions of sulfur oxides (SO 2) into the atmosphere, which can cause acid rain. In fact, these emissions are no longer tolerated at the present time.
It is an object of the present invention to provide a more efficient process for the preparation of tetrahydrothiophene.
The inventors have surprisingly found that the selection of a particular catalyst in relation to a particular temperature range allows for a significant increase in the yield of the reaction.
In other words, the choice of catalyst makes it possible to significantly reduce the temperature of the reaction, making energy saving possible. In addition, the choice of the catalyst allows for an improved yield of the reaction.
Thus, the process for the production of tetrahydrothiophene according to the invention is more economical and exhibits better performance quality, while at the same time being more environmentally friendly.
Disclosure of Invention
Accordingly, one aspect of the present invention is a process for the production of tetrahydrothiophene comprising a stage of reacting 1, 4-butanediol or tetrahydrofuran in the presence of alumina as catalyst comprising a content of sodium oxide of less than 0.3% by weight relative to the total weight of the catalyst, at a temperature between 200 ℃ and 320 ℃, in the gas phase, hydrogen sulfide (H 2 S) and optionally in the presence of carbon dioxide.
Detailed Description
Other features, aspects, objects, and advantages of the present invention will become even more apparent upon reading the following description.
The expressions "from..to..and" and "as used in the present specification are defined. The term" between "is to be understood as including each of the endpoints mentioned.
The process according to the invention comprises a stage of reacting 1, 4-butanediol or tetrahydrofuran in the presence of alumina as catalyst, containing a content of sodium oxide of less than 0.3% by weight relative to the total weight of the catalyst, at a temperature between 200 ℃ and 320 ℃, in the gas phase, in the presence of hydrogen sulphide (H 2 S) and optionally carbon dioxide.
Thus, a gas stream of hydrogen sulfide and 1, 4-butanediol or tetrahydrofuran, each in gaseous form, is introduced into the reactor. These reactants may be fed to the reactor via the same stream or separately. Preferably, the reactants arrive via the same stream, the hydrogen sulphide stream is preheated and a liquid stream of 1, 4-butanediol or tetrahydrofuran is allowed to gasify (vaporise).
Preferably, 1, 4-butanediol is used as reactant.
The reaction is carried out in the gas phase and preferably continuously. The catalyst may be located in a fixed bed in a reactor with trays, the reactor being multitubular or multitubular, isothermal or adiabatic. Multiple injection multi-zone reactors with the same or different catalysts, with or without BDO or THF, or multiple reactors in series may also be used.
The catalyst used is preferably alumina comprising a content of sodium oxide of between 0% and 0.1% by weight, preferably between 0% and 0.08% by weight, and more particularly between 0.03% and 0.08% by weight, relative to the total weight of the catalyst.
The catalyst may comprise a maximum content of alkali metal oxide and alkaline earth metal oxide of less than 0.3 wt.%, relative to the total weight of the catalyst.
In other words, the catalyst used is undoped alumina. Which is pure alumina. The content of sodium oxide of less than 0.3% by weight, relative to the total weight of the catalyst, allows for sodium oxide originating from the process for the preparation of alumina. Preferably, it is not modified before it is introduced into the reactor. In particular, it is not subjected to surface treatment. Thus, according to the method of its preparation, the alumina may comprise sodium oxide, but in a content of less than 0.3% by weight relative to the total weight of the catalyst.
Preferably, when the catalyst is placed in the reactor, the catalyst may be dried using an inert gas such as nitrogen.
Advantageously, the reactants are introduced into the reactor sequentially. Hydrogen sulfide may be introduced first into the reactor and, secondly, 1, 4-butanediol or tetrahydrofuran.
According to a preferred embodiment, the catalyst is placed in a reactor, then dried, followed by first introducing hydrogen sulphide and then second introducing 1, 4-butanediol or tetrahydrofuran into the reactor.
The reaction is advantageously carried out at a temperature between 220 ℃ and 320 ℃, preferably between 220 ℃ and 280 ℃. It is preferably carried out at a pressure of between 1 and 100 bar, preferably between 1 and 50 bar.
Preferably, when 1, 4-butanediol is used as reactant, the molar ratio of hydrogen sulphide relative to 1, 4-butanediol is between 0.1 and 100, preferably between 0.1 and 50, more preferably between 0.5 and 10.
Preferably, when tetrahydrofuran is used as the reactant, the molar ratio of hydrogen sulfide to tetrahydrofuran is between 0.1 and 100, preferably between 0.1 and 50, more preferably between 0.5 and 10.
According to a particular embodiment of the invention, the reaction is carried out at a temperature between 220 ℃ and 280 ℃ in the presence of carbon dioxide in the gas phase.
It has been observed that when carbon dioxide is present in the gas phase, the temperature can also be reduced and the energy costs of the synthesis are also limited.
The process according to the invention may comprise the following successive stages:
b) Condensing the stream obtained from the reaction stage defined above to obtain a tetrahydrothiophene-rich stream and an effluent gas containing non-condensables that may have formed at the end of the preceding stage;
c) At least one stage of purifying the tetrahydrothiophene-rich stream from the preceding stage, preferably by decantation, in which the aqueous phase, the organic phase and the off-gas are separated;
d) Optionally distilling the organic phase from the preceding stage at least once to isolate tetrahydrothiophene from the vent gas;
e) Collecting the tetrahydrothiophene isolated in the preceding stages c) and optionally d),
Stages b) and c) may be sequential or simultaneous.
The process may comprise an intermediate purification stage.
The following examples make it possible to illustrate the invention, but are not limiting in any way.
Examples
Example 1 according to the invention: production of THT from BDO and acid gases (H 2S/CO2)
70Ml (49 g) of a catalyst consisting of alumina containing 700ppm of Na 2 O were introduced into a tubular steel catalytic reactor. The catalyst tested here was from AxensThe height of the catalytic bed was 15cm.
The reactor was fed with 43g/H BDO, 31.1g/H H 2 S and 32.9g/H CO 2.
The pressure in the reactor was kept constant at 3 bar absolute.
The average temperature of the catalytic bed was 225 ℃.
Under these conditions, 100% conversion of BDO and 98% molar yield of THT were obtained.
Example 2 according to the invention: production of THT from BDO and pure H 2 S
70Ml (49 g) of a catalyst consisting of alumina containing 700ppm of Na 2 O were introduced into a tubular steel catalytic reactor. The catalyst tested here was from AxensThe height of the catalytic bed was 15cm.
The reactor was fed with 43g/H BDO and 31.1g/H H 2 S.
The pressure in the reactor was kept constant at 3 bar absolute.
The average temperature of the catalytic bed was 280 ℃.
Under these conditions, 100% conversion of BDO and 98% molar yield of THT were obtained.
It will be noted that the absence of CO 2 does not reduce the performance quality of the reaction compared to example 1.
Comparative example 3: production of THT from BDO and from acid gases (H 2S/CO2)
70Ml (52 g) of a catalyst consisting of alumina containing 4000ppm of Na 2 O were introduced into a tubular steel catalytic reactor. The catalyst tested here was Alumina A2-5 from Axens. The height of the catalytic bed was 15cm.
The reactor was fed with 43g/H BDO, 31.1g/H H 2 S and 32.9g/H CO 2.
The pressure in the reactor was kept constant at 3 bar absolute.
The average temperature of the catalytic bed was 220 ℃.
Under these conditions, 100% conversion of BDO and 82% molar yield of THT were obtained.
The test shows that the use of doped alumina results in a decrease in yield.
Example 4 according to the invention: production of THT from BDO and pure H 2 S
70Ml (49 g) of a catalyst consisting of alumina containing 700ppm of Na 2 O were introduced into a tubular steel catalytic reactor. The catalyst tested here was from AxensThe height of the catalytic bed was 15cm.
The reactor was fed with 43g/H BDO and 31.1g/H H 2 S.
The pressure in the reactor was kept constant at 3 bar absolute.
The average temperature of the catalytic bed was 280 ℃.
Under these conditions, 100% conversion of BDO was obtained.
The stream from this reaction stage is then sent to a condenser. The off-gas is removed and the condensed stream enriched in tetrahydrothiophene is separated by decantation. The aqueous phase is removed and the organic phase is subjected to a distillation stage. Tetrahydrothiophene was recovered in 98% molar yield.
Claims (9)
1. A process for the production of tetrahydrothiophene comprising a stage of reacting 1, 4-butanediol or tetrahydrofuran in the gas phase in the presence of alumina as catalyst, at a temperature between 200 ℃ and 320 ℃, said alumina comprising a content of sodium oxide of less than 0.3% by weight relative to the total weight of the catalyst, in the presence of hydrogen sulfide (H 2 S) and optionally carbon dioxide.
2. Process according to claim 1, characterized in that the alumina comprises a content of sodium oxide of between 0% and 0.1% by weight, preferably between 0% and 0.08% by weight and more particularly between 0.03% and 0.08% by weight, relative to the total weight of the catalyst.
3. Process according to claim 1 or 2, characterized in that the reaction is carried out at a temperature between 220 ℃ and 320 ℃, preferably between 220 ℃ and 280 ℃.
4. Process according to any one of the preceding claims, characterized in that the reaction is carried out at a pressure between 1 and 100 bar, preferably between 1 and 50 bar.
5. Process according to any one of the preceding claims, characterized in that the molar ratio of hydrogen sulphide with respect to 1, 4-butanediol is between 0.1 and 100, preferably between 0.1 and 50, more preferably between 0.5 and 10.
6. Process according to any one of the preceding claims, characterized in that the molar ratio of hydrogen sulphide to tetrahydrofuran is between 0.1 and 100, preferably between 0.1 and 50, more preferably between 0.5 and 10.
7. Process according to any one of the preceding claims, characterized in that the reaction is carried out in the gas phase at a temperature between 220 ℃ and 280 ℃ in the presence of carbon dioxide.
8. Process according to any one of the preceding claims, characterized in that the catalyst comprises a maximum content of alkali metal oxides and alkaline earth metal oxides of less than 0.3% by weight relative to the total weight of the catalyst.
9. Process according to any one of the preceding claims, characterized in that it comprises the following successive stages:
b) Condensing the stream obtained from the stage defined in any one of the preceding claims to obtain a tetrahydrothiophene-rich stream and an effluent gas comprising non-condensables that may have formed at the end of the stage defined in any one of the preceding claims;
c) At least one stage of purifying the tetrahydrothiophene-rich stream from stage b), preferably by decantation, in which the aqueous phase, the organic phase and the off-gas are separated;
d) Optionally distilling the organic phase at least once to isolate tetrahydrothiophene from the vent gas;
e) Collecting the tetrahydrothiophene isolated in stage c) and optionally stage d), stages b) and c) being sequential or simultaneous.
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| FRFR2112997 | 2021-12-06 | ||
| FR2112997A FR3129941A1 (en) | 2021-12-06 | 2021-12-06 | Process for the production of tetrahydrothiophene |
| PCT/FR2022/052248 WO2023105153A1 (en) | 2021-12-06 | 2022-12-05 | Method for producing tetrahydrothiophene |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN118355003A true CN118355003A (en) | 2024-07-16 |
Family
ID=80122434
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202280080367.1A Pending CN118355003A (en) | 2021-12-06 | 2022-12-05 | Process for the preparation of tetrahydrothiophenes |
Country Status (3)
| Country | Link |
|---|---|
| CN (1) | CN118355003A (en) |
| FR (1) | FR3129941A1 (en) |
| WO (1) | WO2023105153A1 (en) |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| SE370076B (en) * | 1969-07-18 | 1974-09-30 | Glanzstoff Ag |
-
2021
- 2021-12-06 FR FR2112997A patent/FR3129941A1/en active Pending
-
2022
- 2022-12-05 WO PCT/FR2022/052248 patent/WO2023105153A1/en active Application Filing
- 2022-12-05 CN CN202280080367.1A patent/CN118355003A/en active Pending
Also Published As
| Publication number | Publication date |
|---|---|
| WO2023105153A1 (en) | 2023-06-15 |
| FR3129941A1 (en) | 2023-06-09 |
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