METHANE SULPHONIC ACID 70%

METHANE SULPHONIC ACID 70%

CAS No. : 75-75-2
EC No. : 200-898-6

Synonyms:
Methanesulfonic acid; Methylsulfonic acid; MSA; 70%; trifluoromethanesulfonic acid; Triflic acid; TFMS; TFSA; HOTf; TfOH; MSA; METHANESULFONIC ACID; 75-75-2; Methylsulfonic acid; Methanesulphonic acid; Mesylate; Methanesulfonicacid; Kyselina methansulfonova; Mesylic acid; Methansulfonsaeure; NSC 3718; CCRIS 2783; UNII-12EH9M7279; Kyselina methansulfonova [Czech]; HSDB 5004; EINECS 200-898-6; CH3SO3H; BRN 1446024; METHANE SULFONIC ACID; Sulfomethane; AI3-28532; CHEBI:27376; 22515-76-0; Methanesulfonic acid, ammonium salt (1:1); 12EH9M7279; Methanesulfonic acid, 98%; Methanesulfonic acid, 99%, extra pure; Methanesulfonic acid, ammonium salt; Methanesulfonic acid, pure, 70% solution in water; Mesic acid; metanesulfonic acid; methansulfonic acid; METHANE SULPHONIC ACID 70%; MsOH; methansulphonic acid; methylsulphonic acid; 03S; methyl sulfonic acid; methyl-sulfonic acid; methane-sulfonic acid; MeSO3H; methane sulphonic acid; methanesulphonic-acid-; MSA 70%; NSC 166292; PubChem2058; PubChem11149; LACTIC ACID(DL); AI3-62914; ammonium methanesulphonate; CH3SO2OH; H3CSO3H; Methane Sulfonic Acid 99%; 4-04-00-00010 (Beilstein Handbook Reference); KSC377E0F; Methanesulfonic acid, 99.5%; Methanesulfonic acid, anhydrous; Methane Sulphonic Acid 70%; $l^{1}-oxidanylsulfonylmethane; Methanesulfonic acid, HPLC grade; NSC3718; Methanesulfonic acid, >=99.0%; [C]S(O)(=O)=O; Methane Sulfonic Acid, 70% Solution; CAS-75-75-2; Methanesulfonic acid, >=99.0%, ReagentPlus(R); Methanesulfonic acid, for HPLC, >=99.5% (T); Methanesulfonic acid solution, 70 wt. % in H2O; Methanesulfonic acid, Vetec(TM) reagent grade, 98%; Methanesulfonic acid solution, 4 M (with 0.2% (w/v) tryptamine); Methanesulfonic acid concentrate, 0.1 M CH3SO3H in water (0.1N), eluent concentrate for IC; Methanesulfonic acid, PharmaGrade, Manufactured under appropriate GMP controls for pharma or biopharmaceutical production

Methane Sulphonic Acid 70%

Methane sulphonic acid 70% (MsOH) or methanesulphonic acid (in British English) is a colorless liquid with the chemical formula CH3SO3H. It is the simplest of the alkylsulfonic acids. Salts and esters of Methane sulphonic acid 70% are known as mesylates (or methanesulfonates, as in ethyl methanesulfonate). It is hygroscopic in its concentrated form. Methane sulphonic acid 70% may be considered an intermediate compound between sulfuric acid (H2SO4), and methylsulfonylmethane ((CH3)2SO2), effectively replacing an –OH group with a –CH3 group at each step. This pattern can extend no further in either direction without breaking down the –SO2– group. Methane sulphonic acid 70% can dissolve a wide range of metal salts, many of them in significantly higher concentrations than in hydrochloric or sulfuric acid.

Applications
Methane sulphonic acid 70% is used as an acid catalyst in organic reactions because it is a non-volatile, strong acid that is soluble in organic solvents. It is convenient for industrial applications because it is liquid at ambient temperature, while the closely related p-toluenesulfonic acid (PTSA) is solid. However, in a laboratory setting, solid PTSA is more convenient.
Methane sulphonic acid 70% can be used in the generation of borane (BH3) by reacting Methane sulphonic acid 70% with NaBH4 in an aprotic solvent such as THF or DMS, the complex of BH3 and the solvent is formed.

Electroplating
Solutions of Methane sulphonic acid 70% are used for the electroplating of tin and tin-lead solders. It is displacing the use of fluoroboric acid, which releases corrosive and volatile hydrogen fluoride.
Methane sulphonic acid 70% is also a primary ingredient in rust and scale removers.[6] It is used to clean off surface rust from ceramic, tiles and porcelain which are usually susceptible to acid attack.

See also
TrifluoroMethane sulphonic acid 70% - the more acidic trifluoro analogue

Reactions
As an acid
In the laboratory, Methane sulphonic acid 70% is useful in protonations because the conjugate base of Methane sulphonic acid 70% is nonnucleophilic. It is also used as an acidic titrant in nonaqueous acid-base titration because it behaves as a strong acid in many solvents (acetonitrile, acetic acid, etc.) where common mineral acids (such as HCl or H2SO4) are only moderately strong.

With a Ka = 5×1014, pKa −14.7±2.0,[1] Methane sulphonic acid 70% qualifies as a superacid. It owes many of its useful properties to its great thermal and chemical stability. Both the acid and its conjugate base CF3SO−
3, known as triflate, resist oxidation/reduction reactions, whereas many strong acids are oxidizing, e.g. perchloric or nitric acid. Further recommending its use, Methane sulphonic acid 70% does not sulfonate substrates, which can be a problem with sulfuric acid, fluorosulfuric acid, and chlorosulfonic acid. Below is a prototypical sulfonation, which HOTf does not undergo:
C6H6 + H2SO4 → C6H5(SO3H) + H2O
Methane sulphonic acid 70% fumes in moist air and forms a stable solid monohydrate, CF3SO3H·H2O, melting point 34 °C.

Salt and complex formation
The triflate ligand is labile, reflecting its low basicity. Trifluoromethanesulfonic acid exothermically reacts with metal carbonates, hydroxides, and oxides. Illustrative is the synthesis of Cu(OTf)2.
CuCO3 + 2 CF3SO3H → Cu(O3SCF3)2 + H2O + CO2
Chloride ligands can be converted to the corresponding triflates:
3 CF3SO3H + [Co(NH3)5Cl]Cl2 → [Co(NH3)5O3SCF3](O3SCF3)2 + 3 HCl
This conversion is conducted in neat HOTf at 100 °C, followed by precipitation of the salt upon the addition of ether.

Organic chemistry
Methane sulphonic acid 70% reacts with acyl halides to give mixed triflate anhydrides, which are strong acylating agents, e.g. in Friedel–Crafts reactions.
CH3C(O)Cl + CF3SO3H → CH3C(O)OSO2CF3 + HCl
CH3C(O)OSO2CF3 + C6H6 → CH3C(O)C6H5 + CF3SO3H
Methane sulphonic acid 70% catalyzes the reaction of aromatic compounds with sulfonyl chlorides, probably also through the intermediacy of a mixed anhydride of the sulfonic acid.

Methane sulphonic acid 70% promotes other Friedel–Crafts-like reactions including the cracking of alkanes and alkylation of alkenes, which are very important to the petroleum industry. These Methane sulphonic acid 70% derivative catalysts are very effective in isomerizing straight chain or slightly branched hydrocarbons that can increase the octane rating of a particular petroleum-based fuel.
Methane sulphonic acid 70% reacts exothermically with alcohols to produce ethers and olefins.
Methane sulphonic acid 70% condensation reaction
Dehydration gives the acid anhydride, trifluoromethanesulfonic anhydride, (CF3SO2)2O.

Safety
Methane sulphonic acid 70% is one of the strongest acids. Contact with skin causes severe burns with delayed tissue destruction. On inhalation it causes fatal spasms, inflammation and edema.
Like sulfuric acid, Methane sulphonic acid 70% must be slowly added to polar solvents to prevent thermal runaway.

Product description Methane Sulphonic Acid (MSA) - 70 % or 100 %
Most common applications:
Chemical synthesis
Metal refinement
Industrial cleaning
Other names:
Methylsulfonic Acid
Methyl Sulfonic Acid
Molecular formula:
CH4O3S
CAS number:
75-75-2

Marinosulfonomonas methylotropha strain TR3 is a marine methylotroph that uses methanesulfonic acid (Methane sulphonic acid 70%) as a sole carbon and energy source. The genes from M. methylotropha strain TR3 encoding methanesulfonate monooxygenase, the enzyme responsible for the initial oxidation of Methane sulphonic acid 70% to formaldehyde and sulfite, were cloned and sequenced. They were located on two gene clusters on the chromosome of this bacterium. A 5.0-kbp HindIII fragment contained msmA, msmB, and msmC, encoding the large and small subunits of the hydroxylase component and the ferredoxin component, respectively, of the methanesulfonate monooxygenase, while a 6.5-kbp HindIII fragment contained duplicate copies of msmA and msmB, as well as msmD, encoding the reductase component of methanesulfonate. Both sets of msmA and msmB genes were virtually identical, and the derived msmA and msmB sequences of M. methylotropha strain TR3, compared with the corresponding hydroxylase from the terrestrial Methane sulphonic acid 70% utilizer Methylosulfonomonas methylovora strain M2 were found to be 82 and 69% identical. The msmA gene was investigated as a functional gene probe for detection of Methane sulphonic acid 70%-utilizing bacteria. PCR primers spanning a region of msmA which encoded a unique Rieske [2Fe-2S] binding region were designed. These primers were used to amplify the corresponding msmA genes from newly isolated Hyphomicrobium, Methylobacterium, and Pedomicrobium species that utilized Methane sulphonic acid 70%, from Methane sulphonic acid 70% enrichment cultures, and from DNA samples extracted directly from the environment. The high degree of identity of these msmA gene fragments, compared to msmA sequences from extant Methane sulphonic acid 70% utilizers, indicated the effectiveness of these PCR primers in molecular microbial ecology.

Methane sulphonic acid 70% and other lower alkanesulfonic acids are useful for plating of lead, nickel, cadmium, silver, and zinc. It also finds use in plating of tin, copper, lead, and other metals and is used in printed circuit board manufacture.
Methane sulphonic acid 70% ... finds use in preparing biological and agricultural chemicals, textile treatment chemicals, and for plastics and polymers.
Methane sulphonic acid 70% finds use in ion-exchange resin regeneration because of the high solubility of many metal salts in aqueous solutions.

Methane sulphonic acid 70% (MSA) soln - containing 50 mg MSA (Eastman Kodak Co No 6320)/mL chloroform; prepn fresh daily.
Methane sulphonic acid 70% is listed as a High Production Volume (HPV) chemical (65FR81686). Chemicals listed as HPV were produced in or imported into the U.S. in >1 million pounds in 1990 and/or 1994. The HPV list is based on the 1990 Inventory Update Rule. (IUR) (40 CFR part 710 subpart B; 51FR21438).

The popularity of Methane sulphonic acid 70% as an electrolyte in electrochemical applications has developed as a result of the following unique physical and chemical properties: (1) exhibits low corrosivity and is easy to handle, (2) nonoxidizing, (3) manufacturing process yields a high purity acid, (4) exceptional electrical conductivity, (5) high solubility of metal salts permits broad applications, (6) Methane sulphonic acid 70%-based formulations are simpler, (7) biodegradable, and (8) highly stable to heat and electrical current.

Acute Exposure/ Both anhydrous and 70% methanesulfonic acid were corrosive to mouse skin by the anesthetized tail method after a 1 hr exposure.
Methane sulphonic acid 70% is an alkanesulfonic acid in which the alkyl group directly linked to the sulfo functionality is methyl. It has a role as an Escherichia coli metabolite. It is an alkanesulfonic acid and a one-carbon compound. It is a conjugate acid of a methanesulfonate.

Electrolysis of a mixture /of hydrogen fluoride and methanesulfonic acid/ produced oxygen difluoride which exploded.
Methane sulphonic acid 70% is too powerful a catalyst for O-alkylation with the vinyl ether, causing explosive polymerisation of the latter on the multimol scale. Dichloroacetic acid is a satisfactory catalyst on the 3 g mol scale.
Methane sulphonic acid 70% is shipped in tank trucks and in plastic 55-gal drums or smaller containers with polyethylene inserts.

Methane sulphonic acid 70% was evaluated in an epidemiology study. The methodology used to assess health effects from potential exposure included a work/family history questionnaire; physical measurements; chest x-ray; pulmonray function tests; general blood chemistries; CBC with indices and differential; urinalysis; urinary phenol; sputum cytology; and a physician's examination. The workforce consisted of 10 male employees. Chest x-rays, sputum cytology, all liver and kidney function tests, and urine pheonol were normal; and no serious blood disorder or skin disorder was reported. It was determined that there was no evidence of hematolgoical, biochemical or clinical aberrations caused by occupational exposures. One person may have an allegic response to contact with cellosolve.

Methane sulphonic acid 70%'s production and use as a catalyst in esterification, alkylation, olefin polymerization, and peroxidation reactions and as a solvent may result in its release to the environment through various waste streams. Methane sulphonic acid 70% is produced by atmospheric hydrolysis of dimethyl sulfoxide, which itself is produced from naturally-derived dimethyl sulfide. If released to air, a vapor pressure of 4.28X10-4 mm Hg at 25 °C indicates methanesulfonic acid will exist solely as a vapor. Vapor-phase methanesulfonic acid will be degraded in the atmosphere by reaction with photochemically-produced hydroxyl radicals; the half-life for this reaction in air is estimated to be 58 days. Methane sulphonic acid 70% does not contain chromophores that absorb at wavelengths >290 nm and therefore is not expected to be susceptible to direct photolysis by sunlight. If released to soil, methanesulfonic acid is expected to have very high mobility based upon an estimated Koc of 1. The pKa of methanesulfonic acid is -1.86, indicating that this compound will exist almost entirely in the anion form in the environment and anions generally do not adsorb more strongly to soils containing organic carbon and clay than their neutral counterparts. Volatilization from moist soil is not expected because the acid exists as an anion and anions do not volatilize. Utilizing the Japanese MITI test, 100% of the Theoretical BOD was reached in four weeks indicating that biodegradation is an important environmental fate process. If released into water, methanesulfonic acid is not expected to adsorb to suspended solids and sediment based upon the estimated Koc. The pKa indicates methanesulfonic acid will exist almost entirely in the anion form at pH values of 5 to 9 and therefore volatilization from water surfaces is not expected to be an important fate process. Methane sulphonic acid 70% is miscible with water and therefore bioconcentration in aquatic organisms is low. Hydrolysis is not expected to be an important environmental fate process since this compound lacks functional groups that hydrolyze under environmental conditions. Occupational exposure to methanesulfonic acid may occur through inhalation and dermal contact with this compound at workplaces where methanesulfonic acid is produced or used. Monitoring data indicate that the general population may be exposed to methansulfonic acid via inhalation of ambient air; methanesulfonic acid is widely detected in marine air. 

Methane sulphonic acid 70% is produced by atmospheric hydrolysis of dimethyl sulfoxide(1), which itself is produced from the atmospheric photochemical oxidation of dimethyl sulfide, which comes from marine algae and salt marsh plants(2).
Methane sulphonic acid 70%'s production and use as a catalyst in esterification, alkylation, olefin polymerization, peroxidation reactions(1) and as a solvent(2) may result in its release to the environment through various waste streams(SRC).

TERRESTRIAL FATE: Based on a classification scheme(1), an estimated Koc value of 1(SRC), determined from a structure estimation method(2), indicates that methanesulfonic acid is expected to have very mobility in soil(SRC). The pKa of methanesulfonic acid is -1.86(3), indicating that this compound will exist almost entirely in the anion form in the environment and anions generally do not adsorb more strongly to soils containing organic carbon and clay than their neutral counterparts(4). Volatilization from moist soil is not expected because the acid exists as an anion and anions do not volatilize. Methane sulphonic acid 70% is not expected to volatilize from dry soil surfaces(SRC) based upon a vapor pressure of 4.28X10-4 mm Hg at 25 °C(5). Utilizing the Japanese MITI test, 100% of the Theoretical BOD was reached in four weeks(6) indicating that biodegradation is an important environmental fate process in soil(SRC).

Based on a classification scheme(1), an estimated Koc value of 1(SRC), determined from a structure estimation method(2), indicates that methanesulfonic acid is not expected to adsorb to suspended solids and sediment(SRC). A pKa of -1.86(3) indicates methanesulfonic acid will exist almost entirely in the anion form at pH values of 5 to 9 and therefore volatilization from water surfaces is not expected to be an important fate process(4). Methane sulphonic acid 70% is miscible with water(5) and therefore bioconcentration in aquatic organisms is low(SRC). Utilizing the Japanese MITI test, 100% of the Theoretical BOD was reached in four weeks(6) indicating that biodegradation is an important environmental fate process in water(SRC).

According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), methanesulfonic acid, which has a measured vapor pressure of 4.28X10-4 mm Hg at 25 °C(2), is expected to exist solely as a vapor in the ambient atmosphere. Vapor-phase methanesulfonic acid is degraded in the atmosphere by reaction with photochemically-produced hydroxyl radicals(SRC); the half-life for this reaction in air is estimated to be 58 days(SRC), calculated from its rate constant of 2.8X10-13 cu cm/molecule-sec at 25 °C(SRC) that was derived using a structure estimation method(3). Methane sulphonic acid 70% does not contain chromophores that absorb at wavelengths >290 nm(4) and therefore is not expected to be susceptible to direct photolysis by sunlight(SRC).

The rate constant for the vapor-phase reaction of methanesulfonic acid with photochemically-produced hydroxyl radicals has been estimated as 2.8X10-13 cu cm/molecule-sec at 25 °C(SRC) using a structure estimation method(1). This corresponds to an atmospheric half-life of about 58 days at an atmospheric concentration of 5X10+5 hydroxyl radicals per cu cm(1). Methane sulphonic acid 70% is not expected to undergo hydrolysis in the environment due to the lack of functional groups that hydrolyze under environmental conditions(2). Methane sulphonic acid 70% does not contain chromophores that absorb at wavelengths >290 nm(2) and therefore is not expected to direct photolysis by sunlight(SRC).

Using a structure estimation method based on molecular connectivity indices(1), the Koc of methanesulfonic acid can be estimated to be 1(SRC). According to a classification scheme(2), this estimated Koc value suggests that methanesulfonic acid is expected to have very high mobility in soil. The pKa of methanesulfonic acid is -1.86(3), indicating that this compound will almost entirely exist in the anion form in the environment and anions generally do not adsorb more strongly to soils containing organic carbon and clay than their neutral counterparts(4).
Methane sulphonic acid 70% is miscible with water(1) and therefore bioconcentration in aquatic organisms is low(SRC).

A pKa of -1.86(1) indicates methanesulfonic acid will exist almost entirely in the anion form at pH values of 5 to 9 and therefore volatilization from water surfaces or moist soil surfaces is not expected to be an important fate process(2). Methane sulphonic acid 70% is not expected to volatilize from dry soil surfaces(SRC) based upon its vapor pressure of 4.28X10-4 mm Hg(3).
Methane sulphonic acid 70% was detected in rainwater ranging from 41.9 (July 1996) to 1325.8 (December 1996) neq/L (volume weighted monthly mean concentrations) collected at Amsterdam Island in the Southern Indian Ocean, sampled from December 1995 to February 1997(1).

Methane sulphonic acid 70% had sub-micrometer-aerosol concentration peaks of approximately 0.47 and 0.4 mol/cu m in February and December, respectively, in the atmosphere at Cape Grim off of Australia in 1989(1). Methane sulphonic acid 70% was found at the highest levels in atmospheric samples collected around noon and concentrated in the smaller size particles (0.25-2 um in diameter) at concentrations of 5.3, 5.5, and 15.7 ng/cu meter in samples taken from the Southern Bahamas, the Northern Bahamas, and the Sargasso Sea, respectively(2). Methane sulphonic acid 70% was found in Germany at concentrations of 0.02 - 0.43 ug/cu m in atmospheric samples taken in October and November of 1978(3). Aerosol methanesulfonic acid was detected at six stations in the Pacific at mean concentrations of 0.097, 0.029, 0.044, 0.026, 0.021, and 0.024 ug/cu m(4). Aerosol methanesulfonic acid has been found at mean concentrations of 9.27X10-9 and 1.14X10-9 mol/cu m in July of 1985 and December of 1986 in the marine atmosphere of the British Isles(5).

Methane sulphonic acid 70% was detected in 62 out of 62 air samples collected from the UK to Antarctica between Mar 10, 1992 to Oct 1, 1993 at concentrations ranging from 1.72 to 362 ng/cu m, average 77 ng/cu m(1). Methane sulphonic acid 70% was detected in 18 out of 18 air samples collected from the UK to the Falkland Islands between Mar 10, 1992 to Jan 11, 1992 at concentrations ranging from 1.72 to 39.7 ng/cu m, average 14.3 ng/cu m(1). Methane sulphonic acid 70% was detected in 44 out of 44 air samples collected from areas south of the Falkland Islands between May 11, 1992 to Oct 1, 1993 at concentrations ranging from 1.94 to 362 ng/cu m, average 103 ng/cu m(1). Methane sulphonic acid 70% was detected in 23 out of 23 air samples collected from the Halley Bay in the east Weddell Sea between Aug 12, 1992 to Oct 1, 1993 at concentrations ranging from 2.48 to 362 ng/cu m, average 136 ng/cu m(1). Methane sulphonic acid 70% was detected in the upper limit of 39 samples collected from the Atlantic ocean between March 1987 to September 1988 at concentrations ranging from 3.9-8.5 ng/cu m(2). Methane sulphonic acid 70% was detected in the upper limit of 4 samples collected from the English channel between April 1987 to September 1988 at concentrations ranging from 13.8-24.3 ng/cu m(2). Methane sulphonic acid 70% was detected in the upper limit of 43 samples collected from the North Sea between April 1986 to April 1989 at concentrations ranging from 12.8 to 66.2 ng/cu m(2).

NIOSH (NOES Survey 1981-1983) has statistically estimated that 8,084 workers (1,393 of these were female) were potentially exposed to methanesulfonic acid in the US(1). Occupational exposure to methane sulfonic acid may occur through inhalation and dermal contact with this compound at workplaces where methanesulfonic acid is produced or used. Monitoring data indicate that the general population may be exposed to methanesulfonic acid via inhalation of ambient air(SRC).

Methane sulphonic acid 70% is an alkanesulphonic acid and its chemical formula is CH3SO3H. MSA is a strong acid having pKa= 1.9 and completely ionized in 0.1 M in an aqueous solution and has small affinity to oxidize organic compounds, less corrosive and toxic than other mineral acids. MSA is also biodegradable and not evolve toxic gases. Therefore MSA is considered as green acid. Therefore its use in organic synthesis attracts many chemists to use in organic synthesis. In this review we described the MSA catalyzed organic transformation.

KEYWORDS:
Methane sulphonic acid 70%; green; catalyst; organic reactions

Physical properties of Methane Sulphoic Acid
Methane sulphonic acid 70% is a clear colourless liquid available as a 70% solution in water and anhydrous form. The structure of methane sulphonic acid lends itself to many catalytic reactions, due to its high acid strength (pKa= -1.9) and low molecular weight (96.0 g/mol).

Methane Sulphonic Acid is Green Acid Catalysts
It is easy to handle methane sulphonic acid as liquid and can be recyclized.
It has low LD50 and biodegradable forming sulphate and CO2.
Methane sulphonic acid 70% is considered to be natural product and is part of the natural sulphur.
It is less corrosive and toxic than other mineral acids.
Due to these properties methane sulphonic acid making an environmentally benign material [1].

About Methane sulphonic acid 70%
Helpful information
Methane sulphonic acid 70% is registered under the REACH Regulation and is manufactured in and / or imported to the European Economic Area, at ≥ 10 000 to < 100 000 per annum.

Methane sulphonic acid 70% is used by consumers, by professional workers (widespread uses), in formulation or re-packing, at industrial sites and in manufacturing.

Consumer Uses
Methane sulphonic acid 70% is used in the following products: washing & cleaning products, air care products, anti-freeze products and lubricants and greases.
Other release to the environment of Methane sulphonic acid 70% is likely to occur from: indoor use as processing aid and outdoor use as processing aid.
Article service life
ECHA has no public registered data on the routes by which Methane sulphonic acid 70% is most likely to be released to the environment. ECHA has no public registered data indicating whether or into which articles the substance might have been processed.

Widespread uses by professional workers
Methane sulphonic acid 70% is used in the following products: metal surface treatment products, pH regulators and water treatment products and laboratory chemicals.
Methane sulphonic acid 70% is used in the following areas: formulation of mixtures and/or re-packaging, health services and scientific research and development.

Methane sulphonic acid 70% is used for the manufacture of: fabricated metal products.
Release to the environment of Methane sulphonic acid 70% can occur from industrial use: in processing aids at industrial sites.
Other release to the environment of Methane sulphonic acid 70% is likely to occur from: indoor use (e.g. machine wash liquids/detergents, automotive care products, paints and coating or adhesives, fragrances and air fresheners), outdoor use and indoor use in close systems with minimal release (e.g. cooling liquids in refrigerators, oil-based electric heaters).

Formulation or re-packing
Methane sulphonic acid 70% is used in the following products: metal surface treatment products.
Release to the environment of Methane sulphonic acid 70% can occur from industrial use: formulation of mixtures, in processing aids at industrial sites, manufacturing of the substance, as an intermediate step in further manufacturing of another substance (use of intermediates), in the production of articles, as processing aid, as processing aid and of substances in closed systems with minimal release.

Uses at industrial sites
Methane sulphonic acid 70% is used in the following products: metal surface treatment products, pH regulators and water treatment products and laboratory chemicals.
Methane sulphonic acid 70% is used in the following areas: formulation of mixtures and/or re-packaging.
Methane sulphonic acid 70% is used for the manufacture of: chemicals.
Release to the environment of Methane sulphonic acid 70% can occur from industrial use: in processing aids at industrial sites, as processing aid, as an intermediate step in further manufacturing of another substance (use of intermediates), formulation of mixtures and in the production of articles.

Manufacture
Release to the environment of Methane sulphonic acid 70% can occur from industrial use: manufacturing of the substance.

Methane sulphonic acid 70% system
Methane sulphonic acid 70% with high acidity is not only the catalyst in the process of chitin acylation, but also is a good solvent for partially acylated chitin. Thus homogeneous acylation of chitin can be achieved in the Methane sulphonic acid 70% system. Norio et al. [75] mixed chitin, Methane sulphonic acid 70%, and glacial acetic acid according to different molar ratios, and reacted it at 0°C overnight to obtain acetylated chitin with different DS. In this experiment, a homogeneous phase is gradually formed as the reaction proceeds, which contributes to further acylation. This reaction should be kept at a low temperature to prevent degradation of chitin in acidic conditions. The acylating agent is not limited to carboxylic acid but also acid chloride. Furthermore, Kaifu et al. [78] mixed the chitin, Methane sulphonic acid 70%, and acid chloride first, then the mixture was reacted at 0°C for 2 h, followed by an overnight reaction at –20°C to obtain acylated chitin. By changing the kind and molar amount of acid chloride, hexanoylation, oxime acylation, and dodecyl acylation of chitin with different DS can be obtained, of which DS can be up to 1.9. In this process, the crystallinity of chitin can be effectively destroyed by further acylation by reacting at –20°C overnight. In general, the acylation ability of the acid chloride is higher than that of the carboxylic acid. The larger the acylation group, the greater the damage to the crystalline region of chitin.

DMSO and Methane sulphonic acid 70%
DMSO and Methane sulphonic acid 70% are two of the most important organic oxidation products of DMS. It is not entirely clear how Methane sulphonic acid 70%, CH3S(O)(O)(OH), forms, but methanesulfinic acid, CH3S(O)(OH)CH3, has been reported during oxidation in OH–DMS systems. Further addition of OH to methanesulfinic acid, followed by reaction with oxygen, can yield Methane sulphonic acid 70%. At lower temperatures found in the Arctic, there are a wide variety of oxidation products of DMS that include the MSA, DMS, and dimethylsulfone, CH3S(O)(O)CH3.

Although DMS is only moderately soluble in rainwater, there has been some interest in the oxidation in the liquid phase, where modeling suggests that the multiphase reactions can be important. Ozone seems to be the most important oxidant, where there is a predicted lifetime for DMS of a few days in clouds. The oxidation reactions offer the potential for these heterogeneous processes to yield more soluble oxidized sulfur compounds, such as DMSO and DMSO2 (Betterton, 1992; Campolongo et al., 1999).

The concentrations of DMSO have been measured in the southern Indian Ocean with mixing ratios that range from 0.3 to 5.8 ppt. Typically, concentrations of DMSO in the air are ~ 1–2% of the DMS concentrations in air (Jourdain and Legrand, 2001). There is a seasonal cycle with a minimum in winter and a maximum in summer similar to that observed for atmospheric DMS (Ayers et al., 1991). There is also a diurnal cycle for DMSO with maximum values around 09:00 and minimum ones during night, which implies OH reactions with DMS as an important source (Sciare et al., 2000). Being soluble DMSO is also found in rainwater with concentrations from 7.0 to 369 nM and a seasonal maximum in the summer following much the same pattern as DMS in the atmosphere (Sciare et al., 1998).

DMSO can readily be removed onto particles and there it can undergo an efficient oxidation through to methanesulfonate. This adds a significant pathway to the gas-phase production of Methane sulphonic acid 70%, which is present largely in the submicron aerosol fraction. Peak summer concentrations are 0.6 ± 0.3 nmol m− 3 and at times this can amount to almost a quarter of the non-sea-salt sulfate in the remote marine atmosphere (Jourdain and Legrand, 2001).

DMSO is also oxidized to SO2, which can then be converted onto non-sea-salt sulfate. The yield probably ranges from 50% to100% in the tropics with the potential for it to be somewhat lower, perhaps 20–40% in mid-latitudes (de Bruyn et al., 2002).

The most important derivative of sulfuric acid is methanesulfonic acid (Methane sulphonic acid 70%), CH3SO3H. Because it has similar physical properties compared to H2SO4, but is much less oxidizing, it is strongly used in electroplating processes. However, the knowledge of noble metal methanesulfonates is very limited. This might have to do with the reduction power of Methane sulphonic acid 70% which leads often to the formation of the elemental metals when their compounds are reacted with the acid. In fact, besides Ag(CH3SO3) only the ternary aurates M[Au(CH3SO3)4] (M = Li, Na, Rb) have been reported up to now.109 They have been prepared by the reactions of Au(OH)3, M2CO3 (M = Li, Na, Rb), and Methane sulphonic acid 70% at elevated temperatures in sealed glass ampoules. In the crystal structures of the tetragonal compounds Li[Au(CH3SO3)4] and Rb[Au(CH3SO3)4], the complex [Au(CH3SO3)4]− anions are linked by the M+ ions in three dimensions. Contrastingly, in the triclinic structure of Na[Au(CH3SO3)4], the complex anions linked into layers that are further connected by weak hydrogen bonds. The thermal decomposition of the compounds leads in a multistep process to elemental gold and the sulfates M2SO4.

Methane sulphonic acid 70% in 1:9 (v/v) dioxane–CH2Cl2 (Kiso et al., 1992b), is primarily used in SPPS. The advantages are as follows: (i) elimination of side-chain protecting groups is reduced compared to the conventional 45% TFA/CH2Cl2 method, and (ii) pyroglutamyl formation from glutamine-containing peptides is similarly decreased relative to the use of 4 N HCl/dioxane. Using the Methane sulphonic acid 70% deprotection system, Kiso et al. (1990a) developed an efficient method for SPPS consisting of in situ neutralization and the rapid coupling reaction using BOP or BOI reagent activation (Kiso et al., 1990a) (Fig. 7). Porcine brain natriuretic peptide (pBNP) was synthesized successfully using this method (Kiso et al., 1992b).

When comparing sulphuric acid versus methane sulphonic acid (Methane sulphonic acid 70%) as eluent (Figure 4), the Methane sulphonic acid 70% separation is good but when using an equivalent strength of sulphuric acid an inferior manganese/magnesium separation is observed. This is due to sulphate forming a weak complex with the divalent cations, calcium, magnesium and manganese resulting in magnesium and calcium, plus manganese and magnesium, eluting more closely. Methane sulphonic acid 70% is the better eluent to choose for such a separation.

Methane sulphonic acid 70% (MSA) is a strong, odourless and less corrosive Acid. Methane sulphonic acid 70% is not harmful to systems, employees, customers, waste management or the environment when used in chemical synthesis, metal refinement or industrial cleaning. It can be used sparingly and saves energy. Additional advantages are the high solubility of its salts, its lack of colour and the fact it is readily biodegradable (according to OECD Directive 301 A). The Acid strength of the organic Methane sulphonic acid 70% is between that of Carboxylic Acids and strong mineral Acids. Since Methane sulphonic acid 70% is odourless, it may also be used in odour-sensitive applications. Its lack of smell also increases safety at work because it does not produce any acrid fumes. Methane sulphonic acid 70% is very suitable for neutralisation of vegetable oils with high FFA content.