CN1165136A

CN1165136A - Method for preparing methyl sulfonic acid

Info

Publication number: CN1165136A
Application number: CN 96115789
Authority: CN
Inventors: 谷传香; 林举才; 丛维民
Original assignee: Individual
Current assignee: Individual
Priority date: 1996-05-14
Filing date: 1996-05-14
Publication date: 1997-11-19

Abstract

A process for preparing methanesulfonic acid which can be used as solvent, catalyst for alkanisation, esterification and polymerization, and passivator for electroplating includes such steps as oxidation reaction of dimethyldithio on H2O2 under the action of catalyst, purifying and vaporizing concentration, and features less by-product, high output rate, low cost, and no environmental pollution.

Description

A kind of method for preparing methanesulfonic

The present invention relates to a kind of preparation method's of organic compound, particularly methanesulfonic preparation method.

Methanesulfonic (Methane sulfonic acid, molecular formula CH ₃SO ₃OH, molecular weight 96.10) be that white is to little yellow liquid or solid, 20 ℃ of fusing points, boiling point 167-167.5 ℃ (10 mmhg), water-soluble, can corrode iron and steel, copper, lead etc., can be widely used in fields such as chemical industry, machinery as catalyzer, the plating passivator of solvent, alkanisation esterification and polyreaction.At present, produce methanesulfonic and adopt chemical synthesis process to obtain, mainly contain two kinds of production methods, a kind of method is to be formed through nitric acid oxidation by methylthiocyanide methylthiocyanate.Technological process is that concentrated nitric acid and exchanged water are heated to 80-88 ℃, gradation adds methylthiocyanide methylthiocyanate, after temperature rises to about 105 ℃, be heated to 120 ℃ of reactions and got crude product in 5 hours, after the exchanged water dilution, transfer to the PH8-9 after-filtration, filtrate has been concentrated into crystallization and has separated out, crystallization methyl alcohol flush away nitrate radical, make methanesulfonic barium, add exchanged water again and boil, add sulfuric acid while hot and decompose, filter the rear filtrate concentrating under reduced pressure and get finished product, another kind method is through chlorination by methyl-isourea, oxidation, hydrolysis forms, and technological process is that methyl-isourea is added in the entry, feeds chlorine in 20-25 ℃, change yellow to solution colour, temperature descends, and then is reaction end, the reaction solution chloroform extraction, extracting solution steams chloroform after drying under 60-65 ℃ of normal pressure, 60-65 ℃ of (20 mmhg) cut collected in underpressure distillation then.Obtain methylsulphonic acid chlorine, it under agitation is added dropwise in 80 ℃ of hot water, be incubated 2 hours, then reaction solution is evaporated to syrupy shape, be evaporated to steaming behind the thin up again and do not go out till the moisture content, get methanesulfonic.It is long that these two kinds of methods exist operational path, needs the 6-7 procedure just can finish, and the use of strong acid and volatile corrosives makes operating environment poor, and waste water is many simultaneously, by product is many, yield is low, involve great expense.

The objective of the invention is to overcome the shortcoming and defect that above-mentioned technology exists, is raw material thereby disclose a kind of with Methyl disulfide and hydrogen peroxide, the method for preparing methanesulfonic that technology is simple, yield is high, cost is low.

The present invention realizes like this, 1-100% concentration methanesulfonic by the 20-200% that accounts for Methyl disulfide (weight percent) is made catalyzer, Methyl disulfide and hydrogen peroxide under normal pressure with 1: 1.80-1.85 ratio (weight percent) is mixed, under temperature 65-100 ℃, insulation reaction 2 hours, adding accounts for reaction solution 0.1-3% (weight percent) barium carbonate after-filtration then, and filtrate forms through evaporation concentration.

The present invention is owing to adopt the finished product as catalyzer, by product is few, foreign matter content is few, owing to reduced the 3-4 end production process, operational path is shortened, and the production cycle shortens, and production cost reduces, yield reaches more than 95%, and it is excellent to have operating environment, non-environmental-pollution, advantage such as energy consumption is low.

Below in conjunction with embodiment the present invention is done and to be described in detail.

Under normal pressure, in 1500 liters of belt stirrer reactors, add Methyl disulfide, hydrogen peroxide and catalyst methane sulfonic acid, methanesulfonic accounts for the 20-200% (weight percent) of Methyl disulfide, concentration is 1-100% (weight percent), the ratio of Methyl disulfide and hydrogen peroxide is 1: 1.80-1.85 (weight percent), controlled temperature is between 65-100 ℃, insulation reaction 2 hours, reaction finishes and adds the 0.1-3% barium carbonate, be used to remove the by product sulfate radical, solids removed by filtration barium sulfate then, filtrate heating evaporation concentrate and obtain the methanesulfonic product.

Because the reaction of Methyl disulfide and hydrogen peroxide must be finished under the condition of acidic substance as catalyzer, join in the reaction solution as a kind of acidic substance with methanesulfonic, can prevent because the adding of other an acidic catalysts, cause the adding of other impurity, reduced purifying technique, the foreign matter content of finished product is reduced.

Embodiment 1 50kg concentration be 50% methanesulfonic in the presence of, be that 50% hydrogen peroxide is put in the reactor with 200kg Methyl disulfide and 724kg concentration, control reaction temperature 65-75 ℃, be incubated 2 hours, discharging 920kg, the sampling analysis result is as follows:

Methanesulfonic 44.13%

Sulfate radical 0.35%

Oxidable thing 0.32%

Add 7kg barium carbonate after-filtration in reaction solution, the filtrate evaporation concentration obtains the 605kg methanesulfonic, and the sampling analysis result is as follows:

Methanesulfonic 65.1%

Sulfate radical 0.03%

Oxidable thing 0.02%

Embodiment 2 synthetic methods are with embodiment 1, and temperature of reaction is 75-85 ℃, discharging 918kg, and the sampling analysis result is as follows:

Methanesulfonic 44.04%

Sulfate radical 0.41%

Oxidable thing 0.09%

Get methanesulfonic 918kg, add 7.94kg barium carbonate after-filtration, the filtrate evaporation concentration obtains the 602kg methanesulfonic, and the sampling analysis result is as follows:

Methanesulfonic 65.2%

Sulfate radical 0.028%

Oxidable thing 0.008%

Embodiment 3 synthetic methods are with embodiment 1, and temperature of reaction is 85-100 ℃, discharging 918kg, and the sampling analysis result is as follows:

Methanesulfonic 42.87%

Sulfate radical 0.78%

Oxidable thing 0.008%

Add 15.2kg barium carbonate after-filtration in reaction solution, the filtrate evaporation concentration obtains the 585kg methanesulfonic, and the sampling analysis result is as follows:

Methanesulfonic 65.2%

Sulfate radical 0.031%

Oxidable thing 0.006%

Claims

1. method for preparing methanesulfonic by Methyl disulfide and hydrogen peroxide, it is characterized in that: make catalyzer by the 1-100% concentration methanesulfonic that accounts for Methyl disulfide 20-200% (weight percent), under normal pressure, Methyl disulfide and hydrogen peroxide are with 1: 1.80-1.85 ratio (weight percent) is mixed, under 65-100 ℃ of temperature condition, insulation reaction 2 hours, adding accounts for reaction solution 0.1-3% (weight percent) barium carbonate after-filtration then, and the filtered liquid evaporation concentration forms.