PRODUCTS

METHANESULPHONIC ACID

Methanesulphonic acid is used to clean off surface rust from ceramic, tiles and porcelain which are usually susceptible to acid attack.
Methanesulphonic acid is used as a catalyst in organic reactions namely esterification, alkylation and condensation reactions due to its non-volatile nature and solubility in organic solvents.
Methanesulphonic acid is also involved in the production of starch esters, wax oxidate esters, benzoic acid esters, phenolic esters, or alkyl esters.

CAS Number: 75-75-2
EC / EINECS number: 200-898-6
MDL Number: MFCD00007518
Name: Methanesulfonic acid (often abbreviated MSA)
IUPAC name: methanesulfonic acid
Molecular formula: CH₄O₃S (sometimes written CH₃SO₃H)
Molecular weight: ≈ 96.11 g/mol

SYNONYMS:
Methanesulfonic acid, MSA, Methanesulphonic acid, Methyl‑sulfonic acid, MsOH, Methylsulfonic acid, Methane sulfonic acid, CH₃SO₃H, Mesylic acid, methanesulfonic acid mesylates kyselina methansulfonova iron (3+)salt methanesulfonic acid methanesulfonic acid, silver (1+) salt, methanesulfonic acid, iron (3+)salt nickel (2+) salt methanesulfonic acid silver (1+) salt methanesulfonic acid MSA sodium salt methanesulfonic acid, methylsulfonic acid, methanesulphonic acid, methanesulfonicacid, kyselina methansulfonova, methansulfonsaeure, ccris 2783, kyselina methansulfonova czech, ch3so3h, methane sulfonic acid, sulfomethane, Methanesulfonic Acid, Lutropur MSA, Lutropure MAS, MCAT 1201, Mesylic acid, Methylsulfonic acid, NSC 3718, Scaleva, methanesulfonic acid, Methylsulfonic acid, MSA, Sulfomethane, Methanesulfonic Acid, Methanesulphonic Acid, Methylsulfonic Acid, Mesylic Acid, Sulfomethane, MsOH, MeSO₃H, Methansulfonsäure, Kyselina methansulfonova, Methylsulphonic Acid, Methane Sulfonic Acid 70%, Mesic Acid, methanesulfonic acid, Methylsulfonic acid, MSA, Sulfomethane, Mesic acid, Methylsulfonic acid, Methylsulfonic acid, Mesylic acid, MSA, Methanesulfonic acid, Methylsulfonic acid, MSA, Mesylic acid, METHANESULFONIC ACID, 75-75-2, Methylsulfonic acid, Methanesulphonic acid, Kyselina methansulfonova, DTXSID4026422, CHEBI:27376, NSC-3718, 12EH9M7279, DTXCID806422, NSC3718, J1.465F, RefChem:6013, 200-898-6, Mesylate, Mesylic acid, MFCD00007518, Sulfomethane, Methansulfonsaeure, CH4O3S, NSC 3718, METHANE SULFONIC ACID, MsOH, 22515-76-0, MSA, Methanesulfonicacid, ammoniummethanesulfonate, CCRIS 2783, Kyselina methansulfonova [Czech], HSDB 5004, EINECS 200-898-6, BRN 1446024, Alkanesulfonate, AI3-28532, UNII-12EH9M7279, metanesulfonic acid, methansulfonic acid, Aliphatic sulfonate, methansulphonic acid, methylsulphonic acid, 03S, methyl sulfonic acid, methyl-sulfonic acid, methane-sulfonic acid, MeSO3H, methane sulphonic acid, methanesulphonic-acid-, Methanesulfonic acidMSA, Nilotinib Impurity 30, LACTIC ACID(DL), CH3SO2OH, H3CSO3H, SCHEMBL105, WLN: WSQ1, EC 200-898-6, SCHEMBL1022, Methanesulfonic acid solution, 4-04-00-00010 (Beilstein Handbook Reference), SCHEMBL124735, SCHEMBL128169, SCHEMBL148135, Methanesulfonic acid, 99.5%, Methanesulfonic acid, anhydrous, SCHEMBL4432863, SCHEMBL8802624, CHEMBL3039600, SCHEMBL30161224, Methanesulfonic Acid (CH3SO3H), METHANESULFONIC ACID [II], METHANESULFONIC ACID [MI], Methanesulfonic acid, HPLC grade, Methanesulfonic acid, >=99.0%, METHANESULFONIC ACID [HSDB], Tox21_201073, STL264182, AKOS009146947, AT25153, CAS-75-75-2, NCGC00248914-01, NCGC00258626-01, BP-12823, FA164682, FM158427, DB-075013, M0093, M2059, Methanesulfonic acid - 70% aqueous solution, NS00004472, EN300-29198, Methanesulfonic acid, >=99.0%, ReagentPlus(R), Methanesulfonic acid, for HPLC, >=99.5% (T), A934985, F152800, Q414168, Methanesulfonic Acid(Discontinued,See C4X-125630), Methanesulfonic acid, Vetec(TM) reagent grade, 98%, F1908-0093, Z281776238, InChI=1/CH4O3S/c1-5(2,3)4/h1H3,(H,2,3,4, Methanesulfonic acid, Methanesulphonic acid, Mesylate, Methylsulfonate, Methane sulfonic acid, MSA, MsOH, MSA, MeSO₃H, METHANESULPHONIC ACID, METHYLSULFONIC ACID, methane-sulfonic acid, Mesylic acid, Sulfomethane, Methylsulfonic acid, Methanesulfonicacid, Methanesulphonic acid, methane sulfonic acid 70%, CH₃SO₃H, Methanesulphonic acid, Methylsulfonic acid, Kyselina methansulfonova, CH3SO3H, NSC 3718, MsOH, MSA, MeSO3H, METHANESULPHONIC ACID, METHYLSULFONIC ACID, acidemethanesulfonique, METHANE SULFONIC ACID 70%, Mesic acid, SULFOMETHANE, Methylsulphonicacid

Methanesulphonic acid is a colorless liquid with the chemical formula CH3SO3H.
Methanesulphonic acid is the simplest of the alkylsulfonic acids.
Salts and esters of Methanesulphonic acid are known as mesylates.

Methanesulphonic acid is hygroscopic in its concentrated form.
Since ca. 2000 Methanesulphonic acid has become a popular replacement for other acids in numerous industrial and laboratory applications, because it: is a strong acid, has a low vapor pressure, is not an oxidant or explosive, like nitric, sulfuric or perchloric acids.

Methanesulphonic acid is an organosulfuric, colorless liquid with the molecular formula CH3SO3H and structure H3C−S(=O)2−OH.
Methanesulphonic acid is the simplest of the alkylsulfonic acids (R−S(=O)2−OH).
Salts and esters of Methanesulphonic acid are known as mesylates (or methanesulfonates, as in ethyl methanesulfonate).

Methanesulphonic acid is hygroscopic in its concentrated form.
Methanesulphonic acid can dissolve a wide range of metal salts, many of them in significantly higher concentrations than in hydrochloric acid (HCl) or sulfuric acid (H2SO4).

Methanesulphonic Acid is a strong, colorless liquid acid widely used in various industrial applications.
Methanesulphonic acid serves as a catalyst in organic synthesis, a cleaning agent in electronics, and a solvent in the pharmaceutical industry.
Its high solubility in water and organic solvents makes Methanesulphonic acid versatile for diverse chemical processes.

Methanesulphonic acid (MSA) is a strong organic acid.
The chemical oxidation of dimetyl sulfide in the atmosphere leads to the formation of Methanesulphonic acid in large quantities.
Methanesulphonic acid undergoes biodegradation by forming CO2 and sulphate.

It is considered a green acid as Methanesulphonic acid is less toxic and corrosive in comparison to mineral acids.
Methanesulphonic acid is an organic acid with the chemical formula CH3SO3H.
Methanesulphonic acid belongs to the group of alkanesulfonic acids and consists of a methyl residue (CH3) and a sulfonic acid residue (SO3H).

Methanesulphonic acid is a clear, colorless liquid that is highly soluble in water.
Methanesulphonic acid (MSA) is a strong biodegradable, odor-free organic acid that is increasingly popular in cleaning formulations.
Methanesulphonic acid has high thermal stability and is easy to handle.

Methanesulphonic acid is VOC-free, phosphate-free, biodegradable, and is completely soluble in water.
Methanesulphonic acid is a strong, odorless organic acid.
Methanesulphonic acid does not oxidize and is prone to rapid biological decomposition, and its salts are easily soluble.

Methanesulphonic acid is sometimes called "green" due to its low toxicity.
Methanesulphonic acid has strong advantages compared to other acids used in household products and industrial chemistry.
One of the most important advantages is low corrosion activity towards plastics and metals, which is extremely important for modern plumbing and coatings.

Much more effective than classic "green" acids: citric, lactic, oxalic, etc.
The presence of a full package of documents allows it to be successfully used in eco-products that are certified by the relevant authorities.
Does not contain chlorine and phosphorus.

Methanesulphonic acid provides an opportunity to solve a wide range of electroplating issues, since most acid salts are well soluble, and the product itself has a very high degree of purification without impurities.
Methanesulphonic acid is an organic acid with the chemical formula CH3SO3H.

Methanesulphonic acid belongs to the group of alkanesulfonic acids and consists of a methyl residue (CH3) and a sulfonic acid residue (SO3H).
Methanesulphonic acid is a clear, colorless liquid that is highly soluble in water.
Methanesulphonic acid is a methanesulfonic acid for use in the electroplating industry and in the manufacture of printed circuit boards.

Methanesulphonic acid is biodegradable acid indicated for sustainable formulations.
Methanesulphonic acid removes oxides and rust stains, solubilizes salts and encrustations, and has a fast cleaning action.
Methanesulphonic acid also acts as a catalyst for polymerization.

It is safe to handle because Methanesulphonic acid is odorless, non-volatile, and does not generate acid mist.
Methanesulphonic acid is a strong, biodegradable, and odorless organic acid that is increasingly popular in cleaning formulations.
Methanesulphonic acid has high thermal stability and is easy to handle.

Methanesulphonic acid is VOC-free, phosphate-free, biodegradable, and completely soluble in water.
Methanesulphonic acid (MSA), a strong organic acid, is produced in large quantities through the chemical oxidation of dimethyl sulfide in the atmosphere.

This green acid, Methanesulphonic acid, undergoes biodegradation, forming CO2 and sulfate.
Unlike mineral acids, Methanesulphonic acid is less toxic and corrosive, making it an environmentally friendly option.
Methanesulphonic acid is generated in significant amounts through the chemical oxidation of dimethyl sulfide in the atmosphere.

Methanesulphonic acid can biodegrade into CO2 and sulfate.
In comparison to mineral acids, Methanesulphonic acid is considered a green acid due to its lower toxicity and corrosiveness.
Moreover, Methanesulphonic acid's aqueous solution serves as a model electrolyte for electrochemical processes.

Methanesulphonic acid, also known as Methanesulfonate or Methanesulphonic acid, chromium (2+) salt, falls into the category of organosulfonic acids.
These acids contain the sulfonic acid group with the general structure RS(=O)2OH (where R is not a hydrogen atom).

Methanesulphonic acid is soluble in water and displays acidic properties.
Methanesulphonic acid (MSA) is recognized as a strong organic acid noted for its low toxicity and effectiveness as a green solvent.

Methanesulphonic acid's characteristics, including low vapor pressure and high boiling point, enhance its suitability for sustainable chemical processes.
Methanesulphonic acid is also used in synthesis, serving both as a catalyst and a solvent in the production of imidazole derivatives, further contributing to its relevance in promoting environmentally friendly practices in chemistry.

USES and APPLICATIONS of METHANESULPHONIC ACID:
Methanesulphonic acid is widely used in chemical industry and related fields due to its strong acidity and good solubility/handling properties.
Catalysis in organic synthesis: Methanesulphonic acid is used as a strong acid catalyst for esterification, polymerization, alkylation and other acid-catalyzed reactions.
Solvent / reaction medium: Because it is liquid and miscible with water/polar solvents, Methanesulphonic acid is used as a reaction medium or solvent in certain processes.

Electroplating / metal finishing: Methanesulphonic acid is used in electroplating baths and metal treatment / plating processes, especially when strong, non-oxidizing acid is needed.
Pharmaceutical / fine chemicals production: Methanesulphonic acid is used in production of active pharmaceutical ingredients (APIs), intermediates, and in processes requiring strong acid catalysis but lower volatility / safer alternatives vs mineral acids.

Polymer / plastics / textile industry: Methanesulphonic acid is employed in polymerization reactions, fiber treatment, coatings (as curing accelerator), and manufacturing of resins or specialized plastics.
Green-chemistry / “greener acid” alternative: Because of its relatively lower volatility and compared with strong mineral acids (sulfuric, hydrochloric), Methanesulphonic acid is considered for cleaner, safer processes in industry

Methanesulphonic acid is a liquid at room temperature, is soluble in many organic solvents, forms water-soluble salts with all inorganic cations and with most organic cations, does not form complexes with metal ions in water, its anion, mesylate, is non-toxic and suitable for pharmaceutical preparations.

The closely related p-toluenesulfonic acid (PTSA) is solid.
Methanesulphonic acid can be used in the generation of borane (BH3) by reacting Methanesulphonic acid with NaBH4 in an aprotic solvent such as THF or DMSO, the complex of BH3 and the solvent is formed.
Solutions of Methanesulphonic acid are used for the electroplating of tin and tin-lead solders.

Methanesulphonic acid is displacing the use of fluoroboric acid, which releases corrosive and volatile hydrogen fluoride.
Methanesulphonic acid is also a primary ingredient in rust and scale removers.
Methanesulphonic acid is used to clean off surface rust from ceramic, tiles and porcelain which are usually susceptible to acid attack.

Methanesulphonic acid is used as a catalyst in organic reactions namely esterification, alkylation and condensation reactions due to its non-volatile nature and solubility in organic solvents.
Methanesulphonic acid is also involved in the production of starch esters, wax oxidate esters, benzoic acid esters, phenolic esters, or alkyl esters.

Methanesulphonic acid reacts with sodium borohydride in presence of polar solvent tetrahydrofuran to prepare borane-tetrahydrofuran complex.
Methanesulphonic acid finds application in batteries, because of its purity and chloride absence.
In pharmaceutical industry, Methanesulphonic acid is used for the manufacturing of active pharmaceutical ingredients like telmisartan and eprosartan.

Methanesulphonic acid is useful in ion chromatography and is a source of carbon and energy for some gram-negative methylotropic bacteria.
Methanesulphonic acid is involved in the deprotection of peptides.
Catalyst in Organic Synthesis: Methanesulphonic Acid is used as a catalyst in esterification and polymerization reactions due to its strong acidic nature and ability to enhance reaction rates.

Cleaning Agent in Electronics: Its non-volatile and non-oxidizing properties make Methanesulphonic acid ideal for cleaning and etching in the electronics industry, ensuring precision and safety.
Solvent in Pharmaceuticals: Methanesulphonic acid acts as a solvent for various pharmaceutical formulations, aiding in the dissolution and stabilization of active ingredients.

Electroplating: Used in electroplating baths, Methanesulphonic Acid provides a stable and efficient medium for metal deposition, improving coating quality.
Water Treatment: Methanesulphonic acid serves as a descaling agent in water treatment processes, effectively removing mineral deposits and enhancing system efficiency.

Methanesulphonic acid offers a powerful and sustainable cleaning solution for various applications, making it a valuable choice for both professional cleaners and everyday users.
Methanesulphonic acid provides fast and powerful cleaning, even against greasy soils.

Methanesulphonic acid also removes lime scale, calcium deposits, and soap rests, as well as improves rust and grime removal.
Methanesulphonic acid is suitable for bathroom cleaners, toilet bowl cleaners, shower cleaners, and rust removers.
Methanesulphonic acid acts as a crosslinking catalyst.

Methanesulphonic acid is a highly active organic acid.
This colorless and odorless methane sulfonic acid, Methanesulphonic acid, forms highly soluble salts.
Methanesulphonic acid is readily biodegradable and sustainable alternative to conventional acids.

Methanesulphonic acid finds application in metal surface treatment in electronics industry.
Industries & Applications of Methanesulphonic acid: Home Care and I&I, Industrial and Institutional Cleaning / Commercial Laundry, Food and Beverage Processing, Industrial Cleaning, Vehicle & Transportation Care.

Methanesulphonic acid is used industrial Formulators, Biofuels / Biodiesel, Bioethanol, Chemical Industry / Ester Production, Sugar Processing, Construction / Concrete Additives, Electronics / Batteries (Lead, LIB, etc.), Leather & Textile / Leather Production, Paints & Coatings / Electrophoretic Paints, UV Cured Resins, Plastics / Polyurethane, PVC/PS/PET/PP, Adhesives & Sealants, Fuels & Lubricants, Metal Surface Treatment, and Pulp & Paper.

Methanesulphonic acid is used as an electrolyte in electroplating baths.
Methanesulphonic acid is used as an electrolyte for tin and tin-lead baths used for coating steel wires and strips, as well as for electronic devices.

Methanesulphonic acid is used in pickling and etching processes, metal recycling, electropolishing, regeneration of ion exchangers and aluminum coloring.
In the chemical industry, Methanesulphonic acid can be used as a catalyst for esterification, condensation and polymerization reactions.

Methanesulphonic acid is useful in ion chromatography and is a source of carbon and energy for some gram-negative methylotropic bacteria.
Methanesulphonic acid is involved in the deprotection of peptides.
Methanesulphonic acid's aqueous solution is used as a representative electrolyte in electrochemical processes.

-Methanesulphonic acid is used in various cleaning applications, including:
*Household cleaners:
Bathroom cleaners, toilet bowl cleaners, shower cleaners, and rust removers.

*Industrial cleaners:
Food and beverage processing, institutional cleaning, vehicle cleaning, and industrial cleaning.

*Laundry detergents:
Commercial laundry applications.

USES, PROPERTIES, BENEFITS & KEY APPLICATIONS of METHANESULPHONIC ACID:
Methanesulphonic acid is valued across many industries because of its unique combination of properties:
Strong acid with non‑oxidizing behavior — unlike strong mineral acids such as nitric or sulfuric acid, Methanesulphonic acid does not oxidize metals or organic materials aggressively; this reduces side‑reactions, corrosion, and unwanted byproducts.

High purity, halogen‑free, no color / odor — since Methanesulphonic acid is produced via a halogen-free process, it's free from halogen‑containing byproducts; this makes it suitable when halogen contamination must be avoided (e.g. electronics, plating, sensitive chemical syntheses).

Excellent solubility and high solubility of its salts — salts of Methanesulphonic acid (metal methanesulfonates, organic methanesulfonates) are often very water-soluble, which helps in cleaning, electroplating, stripping, metal recycling, metal treatment, etc.

Versatility as an acid catalyst — Methanesulphonic acid is widely used as a catalyst in chemical synthesis: esterification, condensation, polymerization, and other reactions where strong acid catalysis is required, offering high selectivity, lower side‑reactions, and improved product quality compared to traditional mineral acid catalysts (e.g. sulfuric acid, p‑toluenesulfonic acid, etc.).

Industrial cleaning & metal surface treatment — Because of strong acidity, high solubility of salts, low vapor pressure (low odor), and non‑oxidizing behavior, Methanesulphonic acid is used in metal cleaning, rust / scale removal, pickling, metal plating baths (e.g. tin plating, tin‑lead plating), electropolishing, stripping, etching, and metal recycling processes.

Cleaning / descaling / limescale removal — Methanesulphonic acid works effectively in formulations for hard surface cleaning, removing limescale, calcium deposits, soap scum, rust — useful in bathroom cleaners, toilet bowl cleaners, shower cleaners, rust removers, etc.

Sustainability / environmental benefits — Compared to harsher inorganic acids (e.g. chlorides, fluorides, sulfuric), Methanesulphonic acid offers lower environmental risk: readily biodegradable, no chloride / halogen by‑products, low total organic carbon, lower VOC, less corrosive (depending on concentration), making it suited for “greener” formulations and cleaner production methods.

Because of this profile, Methanesulphonic acid is increasingly chosen in electronics plating, metal finishing, industrial cleaning, formulation chemistry, catalysis, and “green chemistry” contexts.

PROPERTIES AND USES of METHANESULPHONIC ACID:
*Acid strength:
Methanesulphonic acid is a strong acid with a low pKa, meaning it can easily donate protons.
This property makes Methanesulphonic acid an important catalyst and reagent in organic syntheses.

*Solvent:
Due to Methanesulphonic acid's high solubility in water and organic solvents, Methanesulphonic acid is often used as a reaction medium in various chemical processes.

*Catalyst:
Methanesulphonic acid serves as an efficient catalyst in organic reactions such as esterification, transesterification, cyclization and polymerization.
Methanesulphonic acid accelerates chemical reactions by facilitating the reaction pathway and increasing the reaction rate.

*Removal of hydrogen ions:
Methanesulphonic acid is also used as a dehydrating agent in chemical reactions because it can bind hydrogen ions and thus increase the reaction yield.

*Electrochemistry:
In electrochemistry, Methanesulphonic acid is used as an electrolyte in fuel cells because it has high conductivity and good ion transport capacity.

KEY FEATURES of METHANESULPHONIC ACID:
*Powerful cleaning:
Effectively removes grease, grime, limescale, calcium deposits, and soap scum.

*Sustainable:
Readily biodegradable, making it an environmentally friendly cleaning choice.

*Reduced corrosiveness:
Safer than traditional strong acids, minimizing the risk of damage to surfaces.

*Low vapor pressure:
Methanesulphonic acid minimizes fumes and odors, improving user safety and comfort.

*High dissolving capacity:
Methanesulphonic acid dissolves various types of scale and mineral deposits.

*Synergistic properties:
Methanesulphonic acid works well with other cleaning agents like chelating agents for enhanced cleaning performance.

THE VERSATILITY of METHANESULPHONIC ACID:
Methanesulphonic acid, also known as MSA, may seem inconspicuous at first glance, but its versatility and chemical significance make it a fascinating component of organic chemistry.

This organic acid, Methanesulphonic acid, consisting of a methyl residue and a sulfonic acid residue, is used in various industries and applications.
Its strong acid strength makes Methanesulphonic acid an indispensable catalyst and reagent in organic syntheses and chemical reactions.

In addition to its role as a catalyst, Methanesulphonic acid also serves as a solvent and dehydrating agent in chemical processes.
Methanesulphonic acid is widely used in organic synthesis, electrochemistry and even medicine.
In organic chemistry, Methanesulphonic acid is an indispensable tool for accelerating and controlling reactions.

Methanesulphonic acid enables the production of complex molecules and contributes to the efficiency and yield of many synthetic processes.
The use of Methanesulphonic acid spans various industries and applications, from pharmaceutical production to electrochemistry.
Its versatility and chemical properties make it a key element in modern chemistry.

Overall, Methanesulphonic acid is a remarkable example of the power and versatility of organic compounds.
Its ability to accelerate and control chemical reactions makes Methanesulphonic acid an indispensable tool for chemists and researchers around the world.

HISTORY AND SYNTHESIS of METHANESULPHONIC ACID:
Early history
German chemist Hermann Kolbe discovered Methanesulphonic acid between 1842 and 1845 and originally termed it methyl hyposulphuric acid.
The discovery stemmed from earlier work by Berzelius and Marcet in 1813, who treated carbon disulfide with moist chlorine and produced a compound they named "sulphite of chloride of carbon".

By reacting Methanesulphonic acid with barium hydroxide Kolbe demonstrated it to actually be trichloromethylsulfonyl chloride (CCl₃SO₂Cl in modern notation).
2 CCl3SO2Cl + 3 Ba(OH)2 → Ba(CCl3SO3)2 + 3 BaCl2 + 2 H2O

From resulting barium trichloromethylsulfonate Kolbe isolated the free acid, which he was then able to sequentially dechlorinate by electrolytically generated atomic hydrogen to ultimately yield Methanesulphonic acid.
CCl3SO3H + 3 H → CHCl2SO3H + 2 H + HCl → … → CH3SO3H + 3 HCl

Kolbe's research on methanesulfonic and chloroacetic acids was hailed by Berzelius as strong evidence for his theory of copulated compounds, a modification of radical theory to accommodate substitution reactions which posited the combination of organic and inorganic moieties without significantly altering the properties of the latter.

Later in the 19th century, the name transitioned to methyl sulphonic acid.
Other historical laboratory synthesis routes included oxidizing methanethiol, dimethyl disulfide or methyl thiocyanate with nitric acid.

ADVANTAGES of METHANESULPHONIC ACID:
• Strong organic acid.
• Does not oxidize.
• Low corrosive activity towards plastics and metals.
• Odorless.
• Colorless.
• Prone to rapid biological decomposition.
• High thermal stability.
• Does not form toxic vapor.
• Resistant to hydrolysis.
• Easy to use.
• Does not contain phosphorus.

INDUSTRIAL PRODUCTION of METHANESULPHONIC ACID:
The first commercial production of Methanesulphonic acid, developed in the 1940s by Standard Oil of Indiana, was based on oxidation of dimethylsulfide by O2 from air.
Although inexpensive, this process suffered from a poor product quality and explosion hazards.

Starting from the 1960s, it received a shortened name of mesylic acid after the term for the "mesyl" group coined by Helferich et al. in 1938.
In 1967, the Pennwalt Corporation (USA) developed a different process for dimethylsulfide (as a water-based emulsion) oxidation using chlorine, followed by extraction-purification.

In 2022 this chlorine-oxidation process was used only by Arkema (France) for making high-purity Methanesulphonic acid.
This process is not popular on a large scale, because it co-produces large quantities of hydrochloric acid.

Between years 1970 and 2000 Methanesulphonic acid was used only on a relatively small-scale in niche markets (for example, in the microelectronic and electroplating industries since the 1980s), which was mainly due to its rather high price and limited availability.

However, this situation changed around 2003, when BASF launched commercial production of Methanesulphonic acid in Ludwigshafen based on a modified version of the aforementioned air oxidation process, oxidising dimethyldisulfide with nitric acid which is then restored using atmospheric oxygen.

The former is produced in one step from methanol from syngas, hydrogen and sulfur.
An even better (lower-cost and environmentally friendlier) process of making Methanesulphonic acid was developed in 2016 by Grillo-Werke AG (Germany).

Methanesulphonic acid is based on a direct reaction between methane and oleum at around 50 °C and 100 bar in the presence of a potassium persulfate initiator.
Further addition of sulfur trioxide gives Methanesulphonic acid instead.
This technology was acquired and commercialized by BASF in 2019.

BENEFITS of METHANESULPHONIC ACID:
Biodegradable.
Methanesulphonic acid's high level of purity prevents corrosion problems on metal surfaces.
A major advantage in cleaning processes is its strength to dissolve organic and inorganic salts and rust, and the fact that Methanesulphonic acid does not generate toxic fumes.
High thermal stability and high conductivity.

NOTES of METHANESULPHONIC ACID:
Methanesulphonic acid is moisture, light and heat sensitive.
Methanesulphonic acid is hygroscopic.
Keep Methanesulphonic acid container tightly closed in a dry and well-ventilated place.
Methanesulphonic acid is incompatible with amines, strong reducing agents, ethyl vinyl ether, hydrofluoric acid, strong oxidizing agents and bases.

ADDITIONAL CHARACTERISTICS & NOTES of METHANESULPHONIC ACID:
Methanesulphonic acid is one of the simplest alkan-sulfonic acids (smallest: methyl group + sulfonic acid group).
Compared with many strong mineral acids (e.g. sulfuric acid), Methanesulphonic acid is often considered a “greener” or more user-friendly acid in organic synthesis: easier to handle, lower vapor pressure, less oxidizing.

Methanesulphonic acid is stable in water (miscible), alcohols, ethers — useful for many synthetic applications.
Because of its strong acidity and good solubility, Methanesulphonic acid is widely adopted in specialized chemical industries, electroplating, polymerization, pharmaceuticals, etc.

PHYSICAL and CHEMICAL PROPERTIES of METHANESULPHONIC ACID:
CAS: 75-75-2
IUPAC Name: methanesulfonic acid
Molecular Formula: CH4O3S
InChI Key: AFVFQIVMOAPDHO-UHFFFAOYSA-N
SMILES: CS(O)(=O)=O
Molecular Weight (g/mol): 96.10
Form: Liquid
Appearance (Color): Clear colorless
Assay (Aqueous acid-base Titration): ≥68.5 to ≤71.5%
Linear Formula: CH3SO3H
CAS Number: 75-75-2

Molecular Weight: 96.11
Beilstein: 1446024
MDL number: MFCD00007518
UNSPSC Code: 12352100
PubChem Substance ID: 24870724
NACRES: NA.21
CAS Number: 75-75-2
Formula: CH4O3S
Formula Weight: 96.11
Linear Formula: CH3SO3H
MDL No.: MFCD00007518

Density: 1.319 g/mL at 25 C
Refractive Index: n20/D 1.416
Beilstein Registry Number: 1446024
UNSPSC Code: 12352100
CAS No: [75-75-2]
Product Code: FM158427
MDL No: MFCD00007518
MOL file: Download
Chemical Formula: CH4O3S
Molecular Weight: 96.11 g/mol
Smiles: CS(=O)(=O)O

Melting Point: 18 °C
Boiling Point: 167 °C
Density: 1.481 g/cm3
Flash Point: 189 °C
Density: 1.483 (204 c)
Direct Evaporative Cooling: 200 c
Vapor Pressure: 1 mm hg (20 c)
Melting Point: 20 c
Refractive Index: 1.4300
Molecular weight: 96.10

Color: colorless to yellowish liquid
Flash Point: 110 c
Solubility: water, alcohol, ether, oxygenated solvs.
Boiling Point: 167 c (10 mm)
Molecular Formula / Molecular Weight: CH4O3S = 96.10
Physical State (20 deg.C): Liquid
Storage Temperature: Room Temperature (Recommended in a cool and dark place, <15°C)
Store Under Inert Gas: Store under inert gas

Condition to Avoid: Hygroscopic
CAS RN: 75-75-2
Reaxys Registry Number: 1446024
PubChem Substance ID: 87572203
SDBS (AIST Spectral DB): 4261
Merck Index (14): 5954
MDL Number: MFCD00007518
Appearance: Colorless to pale yellow liquid
Odor: Characteristic

Melting Point: 17–19 °C
Boiling Point: 167 °C at 10 mmHg
Density: 1.481 g/cm³ at 25 °C
Solubility: Miscible with water, ethanol,
tetrahydrofuran, and dimethyl sulfoxide;
limited solubility in toluene and n-hexane
pKa: −1.9 (strong acid)
LogP: −2.424
Flash Point: 230 °F

Refractive Index: n 20/D 1.429
Vapor Pressure: 1 mm Hg at 20 °C
Hygroscopicity: Hygroscopic in concentrated form
Chemical Name: Methanesulfonic Acid
CAS Number: 75-75-2
EC Number: 200-898-6
Molecular Formula: CH₄O₃S
Molecular Weight: 96.11 g/mol
Structure: CH₃SO₃H
Density: 1.483 (204 c)

Direct Evaporative Cooling: 200 c
Melting Point: 20 c
Vapor Pressure: 1 mm hg (20 c)
Refractive Index: 1.4300
Molecular weight: 96.10
Color: colorless to yellowish liquid
Flash Point: 110 c
Solubility: water, alcohol, ether, oxygenated solvs.
Boiling Point: 167 c (10 mm)

CAS Number: 75-75-2
Molecular Weight: 96.11
Beilstein/REAXYS Number: 1446024
EC Number: 200-898-6
MDL number: MFCD00007518
PubChem Substance ID: 24870726
NACRES: NA.21
CAS Number: 75-75-2
Purity: ≥ 99% (Assay by titration)
Molecular Formula: CH4O3S

Molecular Weight: 96.11
MDL Number: MFCD00007518
PubChem ID: 6395
Melting Point: 17 - 20 °C
Density: 1.48
Appearance: Clear colorless to light yellow liquid
Boiling Point: 121 - 123 °C/1 mmHg
Refractive Index: n20/D 1.430
Conditions: Store at RT

Appearance: Colourless to light yellow liquid (solid at low temperatures/melting ~17-20 °C)
Melting point (freezing point): ~17-20 °C (some sources list ~18 °C)
Boiling point: ~167 °C (at reduced pressure ~10 mmHg / 13.3 kPa)
Density: ~1.48 g/cm³ at ~20 °C
Refractive index: ~ nᵈ₁₆/₂₀ ≈ 1.43
Solubility: Highly soluble in water (e.g., 1000 g/L at 20 °C) and miscible with many polar solvents; insoluble or very slightly soluble in alkanes, benzene, toluene.

pKₐ: The acid is very strong; pKₐ values reported around –1.9 in water.
Partition coefficient (log Kₒw): ~ –2.38
Vapour pressure: Very low at ambient temperature (virtually negligible vapour pressure)
Auto-ignition temperature: ~535 °C (ECHA data)
Oxidising properties: None (i.e., it does not act as an oxidising acid)
Characteristics / special remarks:

Because of the sulfonic acid group, MSA is a strong acid but unlike many mineral acids it is non-oxidising, and it forms stable salts (methanesulfonates or mesylates) that are often used in synthesis or in pharmaceuticals.
It is considered “green” relative to some alternatives because of lower volatility, compatibility with many substrates, and favorable environmental/toxicity profile in comparison to strong mineral acids (though it is still hazardous).
Linear Formula: CH3SO3H
CAS Number: 75-75-2
Molecular Weight: 96.11
Beilstein: 1446024
EC Number: 200-898-6

MDL number: MFCD00007518
UNSPSC Code: 12352100
PubChem Substance ID: 24870726
NACRES: NA.21
Chemical formula: CH4O3S
Molar mass: 96.10 g·mol−1
Appearance: Clear, colourless liquid
Density: 1.48 g/cm3
Melting point: 17 to 19 °C (63 to 66 °F; 290 to 292 K)

Boiling point: 167 °C (333 °F; 440 K) at 10 mmHg, 122 °C/1 mmHg
Solubility in water: miscible
Solubility: Miscible with methanol, diethyl ether.
Immiscible with hexane
log P: −2.424
Acidity (pKa): −1.9
Molecular Weight: 96.11 g/mol
XLogP3-AA: -0.9
Hydrogen Bond Donor Count: 1

Hydrogen Bond Acceptor Count: 3
Rotatable Bond Count: 0
Exact Mass: 95.98811516 Da
Monoisotopic Mass: 95.98811516 Da
Topological Polar Surface Area: 62.8 Å²
Heavy Atom Count: 5
Formal Charge: 0
Complexity: 92.6
Isotope Atom Count: 0

Defined Atom Stereocenter Count: 0
Undefined Atom Stereocenter Count: 0
Defined Bond Stereocenter Count: 0
Undefined Bond Stereocenter Count: 0
Covalently-Bonded Unit Count: 1
Compound Is Canonicalized: Yes
Physical state: liquid
Color: light yellow
Odor: characteristic

Melting point/freezing point: Melting point/range: 17 - 19 °C - lit.
Initial boiling point and boiling range: 167 °C at 13 hPa - lit.
Flammability (solid, gas): No data available
Upper/lower flammability or explosive limits:
Upper explosion limit: 24,3 %(V)
Lower explosion limit: 11,4 %(V)
Flash point: 189 °C - closed cup - DIN 51755 Part 1
Autoignition temperature: 535 °C at 1.010 hPa - DIN 51794
Decomposition temperature: No data available
pH: < 1 at 20 °C

Viscosity:
Viscosity, kinematic: 7,86 mm2/s at 25 °C
Viscosity, dynamic: 11,6 mPa.s at 25 °C
Water solubility: ca.1.000 g/l at 20 °C - completely miscible
Partition coefficient: n-octanol/water: log Pow: -2,38 at 20 °C
Bioaccumulation is not expected.
Vapor pressure: 0,112 hPa at 80 °C - OECD Test Guideline 104
Density: 1,481 g/cm3 at 25 °C - lit.
Relative density: No data available
Relative vapor density: No data available
Particle characteristics: No data available

Explosive properties: No data available
Oxidizing properties: none
Dissociation constant: -1,54 at 25 °C
Relative vapor density: 3,32 - (Air = 1.0)
Density: ~1.35 g/cm³ (70% solution at 20°C)
Melting Point (pure): 20°C
Boiling Point: ~167°C (pure compound)
pKa: ~–1.9 (strong acid)
Solubility in Water: Fully miscible
Solubility in Other Solvents: Miscible with alcohols, ethers, and polar organics
Odor: Mild or faintly sour

Name: Methanesulfonic acid (often abbreviated MSA)
IUPAC name: methanesulfonic acid
Molecular formula: CH₄O₃S (sometimes written CH₃SO₃H)
Molecular weight: ≈ 96.11 g/mol
CAS number: 75-75-2
EC / EINECS number: 200-898-6
Physical state / appearance: At room temperature, MSA is a clear, colourless (or very lightly coloured) liquid. As a pure substance it may appear slightly viscous.
Melting point / Freezing point: ~ 17–19 °C
Boiling point: Reported as 167 °C at reduced pressure (10–13 mmHg) in some sources.

Density (liquid): ~ 1.48 g/cm³ (at ~18–25 °C)
Log P (octanol/water partition coefficient): Negative (≈ –2.4), indicating high hydrophilicity / good water miscibility.
Solubility: Fully miscible with water; also miscible with some polar solvents like alcohol or diethyl ether;
insoluble in non-polar solvents like alkanes / benzene / toluene.
Acidity: MSA is a strong sulfonic acid; pKa reported around –1.9 to –2.6 (strong acid).
Stability / Reactivity: Stable under normal conditions; but strongly corrosive, especially toward metals (iron, copper, lead, etc.) — metal contact should be avoided.
Hygroscopic / Sensitive to Moisture: MSA is reportedly hygroscopic / moisture-sensitive; care in storage to avoid water uptake.
Phase behavior: Commercial MSA is available either as anhydrous (> 99.5% purity) or as a concentrated aqueous solution

FIRST AID MEASURES of METHANESULPHONIC ACID:
-Description of first-aid measures
*General advice:
Show this material safety data sheet to the doctor in attendance.
*If inhaled:
After inhalation:
Fresh air.
*In case of skin contact:
Take off immediately all contaminated clothing.
Rinse skin with
water/ shower.
*In case of eye contact:
After eye contact:
Rinse out with plenty of water.
Call in ophthalmologist.
Remove contact lenses.
*If swallowed:
After swallowing:
Immediately make victim drink water (two glasses at most).
Consult a physician.
-Indication of any immediate medical attention and special treatment needed.
No data available

ACCIDENTAL RELEASE MEASURES of METHANESULPHONIC ACID:
-Environmental precautions:
Do not let product enter drains.
-Methods and materials for containment and cleaning up:
Cover drains.
Collect, bind, and pump off spills.
Observe possible material restrictions.
Take up dry.
Dispose of properly.
Clean up affected area.

FIRE FIGHTING MEASURES of METHANESULPHONIC ACID:
-Extinguishing media:
*Suitable extinguishing media:
Carbon dioxide (CO2)
Foam
Dry powder
*Unsuitable extinguishing media:
For this substance/mixture no limitations of extinguishing agents are given.
-Further information:
Prevent fire extinguishing water from contaminating surface water or the ground water system.

EXPOSURE CONTROLS/PERSONAL PROTECTION of METHANESULPHONIC ACID:
-Control parameters:
--Ingredients with workplace control parameters:
-Exposure controls:
--Personal protective equipment:
*Eye/face protection:
Use equipment for eye protection.
Safety glasses
*Body Protection:
protective clothing
*Respiratory protection:
Recommended Filter type: Filter A
-Control of environmental exposure:
Do not let product enter drains.

HANDLING and STORAGE of METHANESULPHONIC ACID:
-Conditions for safe storage, including any incompatibilities:
*Storage conditions:
Tightly closed.
Dry.

STABILITY and REACTIVITY of METHANESULPHONIC ACID:
-Chemical stability:
The product is chemically stable under standard ambient conditions (room temperature).
-Possibility of hazardous reactions:
No data available