阅读说明：本技术 连续合成烷烃磺酸的工业方法 (Industrial method for continuous synthesis of alkane sulfonic acid ) 是由 J-L·迪博瓦 于 2019-02-20 设计创作，主要内容包括：本发明涉及由相应的烷烃和三氧化硫连续工业制备烷烃磺酸的方法,所述方法在为所述烷烃磺酸的溶剂中进行。(The present invention relates to a process for the continuous industrial preparation of alkanesulfonic acids from the corresponding alkanes and sulfur trioxide, said process being carried out in a solvent which is said alkanesulfonic acid.)

1. For slave formula C_nH_2n+2Continuous industrial preparation of alkanes of formula C_nH_2n+1SO₃H, wherein n represents an integer from 1 to 20 inclusive, preferably from 1 to 12 inclusive, more preferably from 1 to 6 inclusive, for example equal to 1, 2 or 3, said process comprising at least the following steps:

a) alkane sulfonic acid C_nH_2n+1SO₃H, wherein n is as defined above,

b) heating the alkanesulfonic acid to a temperature of from 25 ℃ to 120 ℃, preferably from 25 ℃ to 100 ℃, more preferably from 25 ℃ to 70 ℃,

c) sulfur trioxide is introduced in an amount such that the (alkanesulfonic acid)/(sulfur trioxide) molar ratio is from 70/30 to 95/5,

d) the alkane is introduced at a pressure of from 4MPa to 15MPa, preferably from 5MPa to 12MPa,

d) introducing a free radical initiator into the reaction kettle,

e) the reaction is carried out continuously by simultaneously, sequentially or alternately carrying out the following three substeps e1), e2) and e 3):

e1) adding sulfur trioxide to maintain the initial molar ratio of (alkanesulfonic acid)/(sulfur trioxide) as defined in step c),

e2) the alkane is added so as to maintain a (alkane)/(sulfur trioxide) molar ratio of 4/1 to 2/1, preferably 3.5/1 to 2.5/1, typically so that the (alkane)/(sulfur trioxide) molar ratio remains about equal to 3, and

e3) continuously withdrawing formula C_nH_2n+1SO₃Alkanesulfonic acids of H, and

f) recovery of formula C after optional separation of unreacted reagents and possible undesired by-products_nH_2n+1SO₃Alkane sulfonic acid of H.

2. The process according to claim 1, wherein the reaction temperature is from 25 ℃ to 120 ℃, preferably from 25 ℃ to 100 ℃, more preferably from 25 ℃ to 70 ℃, from 30 ℃ to 60 ℃, such as about 50 ℃.

3. The process according to claim 1, wherein the reaction pressure is from 4MPa to 15MPa, preferably from 5MPa to 12 MPa.

4. The process according to claim 1, wherein the reactor is selected from reactors provided with a recirculation loop, reactors with self-priming turbines, reactors provided with a so-called venturi system, rotating bed reactors, tubular reactors and the like.

5. A process according to claim 1, wherein the free-radical initiator is selected from the group consisting of azo-bis-iso-butyronitrile, inorganic or organic peroxides, mercury sulfate (HgSO)₄) Palladium sulfate, cesium sulfate, K₂P₂O₈，CaO₂Halogen, preferably selected from formula C_nH_2n+1SO₂-OO-SO₂OC_nH_2n+1Wherein n is as defined above, formula C_nH_2n+1-SO₂-OO-SO₂(iii) initiators of OX, wherein n is as defined above and X represents hydrogen, an alkali or alkaline earth metal, zinc or aluminium, peroxomonosulphuric acid and salts thereof with one or more alkali or alkaline earth metals, and Marshall acid and salts thereof with one or more alkali or alkaline earth metals.

6. The process of claim 1 wherein the alkane and sulfur trioxide are added with consumption of the alkane and sulfur trioxide and the amount of alkanesulfonic acid withdrawn while maintaining (formula C)_nH_2n+2The alkane)/(sulfur trioxide) molar ratio is comprised between 4/1 and 2/1, preferably between 3.5/1 and 2.5/1, typically equal to about 3, and the (alkanesulfonic acid)/(sulfur trioxide) molar ratio is maintained between 70/30 and 95/5.

7. The process of claim 1, wherein the solvent is methanesulfonic acid, the alkane is methane, and the product continuously withdrawn is methanesulfonic acid.

8. A reaction medium comprising formula C_nH_2n+1SO₃Alkanesulfonic acids of H, wherein n is an integer from 1 to 20, inclusive, preferably an integer from 1 to 12, inclusive, more preferably an integer from 1 to 6, inclusive, e.g. equal to 1, 2 or 3, sulfur trioxide, SO₃And formula C_nH_2n+2Wherein n is as defined above, in the reaction medium:

- (alkanesulfonic acid)/(SO)₃) A molar ratio of 70/30 to 95/5, and

- (alkane)/(SO)₃) The molar ratio is 4/1 to 2/1, preferably 3.5/1 to 2.5/1, typically equal to about 3.

9. The reaction medium of claim 8, comprising methanesulfonic acid (CH)₃SO₃H) Sulfur trioxide SO₃And methane (CH)₄) Wherein:

- (methanesulfonic acid)/(SO)₃) A molar ratio of 70/30 and 95/5, and

- (methane)/(SO)₃) The molar ratios are 4/1 and 2/1, preferably 3.5/1 and 2.5/1, generally equal to about 3.

Examples：

The following methods were carried out:

a) methanesulfonic Acid (AMS) is fed to a stirred continuous reactor under pressure in steady operation,

b) methanesulfonic acid is heated to a temperature of about 50 c,

c) sulfur trioxide is introduced in an amount such that the molar ratio (AMS)/(sulfur trioxide) is 80/20,

d) the methane is introduced under pressure and the mixture is,

d) continuous introduction of the initiator CH₃-SO₂O-O-SO₂OH，

e) The reaction is carried out continuously by carrying out the following three substeps e1), e2) and e3) simultaneously, sequentially or alternately:

e1) sulfur trioxide was added to maintain the (AMS)/(sulfur trioxide) molar ratio of 80/20,

e2) adding methane to maintain the (methane)/(sulfur trioxide) molar ratio at about 3, and

e3) methanesulfonic acid was continuously taken out.