Cas no: 5329-14-6  

Sulfamic acid, also known as amidosulfonic acid,amidosulfuric acid,aminosulfonic acid, andsulfamidic acid, is a molecular compound with the formula H3NSO3. 

 

SULPHAMIC ACID = SULFAMIC ACID = AMIDOSULFONIC ACID

Synonyms

sulphamic acid

Amidosulfonic acid

Amidosulfuric acid

Aminosulfonic acid

CAS: 5329-14-6

EINECS: 226-218-8

Sulphamic acid also called sulfamic acid is a white crystalline solid which is stable and non-hygroscopic. Sulfamic Acid is soluble in water and formamide and slightly soluble in methanol, ether, acetone and concentrated sulphuric acid. 

Sulfamic Acid is classified as a strong inorganic acid and is commercially produced from urea and fuming sulphuric acid. 

At room temperature, dilute aqueous sulphamic acid solution is stable for a long time but rapid hydrolysis occurs at elevated temperatures. 

It's solution is less corrosive toward metals than other mineral acids like hydrochloric acid. 

Sulfamic acid possesses a scale solubilising capacity which makes it ideal for removal of scale from boilers, cooling towers, coils, heat exchangers, condensers and a wide range of heating and cooling systems thereby increasing the efficiency of plant and equipment.

Sulphamic acid is used as an acidic cleaning agent, typically for metals and ceramics. 

Sulfamic Acid is a replacement for hydrochloric acid for the removal of rust. In households, Sulfamic Acid is often found as a descaling agent in detergents, cleaners and toilet cleaners for the removal of limescale.

Sulfamic acid is the simplest of the sulfamic acids consisting of a single sulfur atom covalently bound by single bonds to hydroxy and amino groups and by double bonds to two oxygen atoms.

Sulfamic acid is mainly a precursor to sweet-tasting compounds. Reaction with cyclohexylamine followed by addition of NaOH gives C6H11NHSO3Na, sodium cyclamate. 

Related compounds are also sweeteners, see acesulfame potassium.

​Sulfamates have been used in the design of many types of therapeutic agents such as antibiotics, nucleoside/nucleotide human immunodeficiency virus (HIV) reverse transcriptase inhibitors, HIV protease inhibitors (PIs), anti-cancer drugs (steroid sulfatase and carbonic anhydrase inhibitors), anti-epileptic drugs, and weight loss drugs.

Sulfamic Acid is also known as Sulphamic Acid, Amidosulfonic acid, Amidosulfuric acid, Minosulfonic acid, or Sulfamidic acid.

Sulfamic is a molecular compound with the formula H3NSO3. Sulfamic is a dry, non-volatile, non-hygroscopic, stable solid. Sulfamic is soluble in water and forms a strongly acidic aqueous solution that is comparable in acidity to the common strong mineral acids, but it can be safely handled and stored in the dry form. 

The CAS Number for Sulfamic acid is 5329-14-6.

The main reason why Sulfamic Acids is used in oil and gas drilling is to reduce the pH of used extraction fluids and compounds prior to the disposal of these fluids. 

The benefits of using Sulphamic Acid is its ease of handling, solubility and low corrosiveness.

Sulfamic acid can also be used as an acidic cleaning agent, sometimes on its own or mixed with other products, typically for metals and ceramics. Sulfamic is frequently used for removing rust and limescale.

Sulfamic acid is produced industrially by treating urea with a mixture of sulfur trioxide and sulfuric acid (or oleum). Sulfamic acid melts at 205 °C before decomposing at higher temperatures to water, sulfur trioxide, sulfur dioxide and nitrogen.

Sulfamic acid

Sulfamic acid, also known as sulfamic acid, is an inorganic sulfide acid. 

SULFAMIC ACID

5329-14-6

Amidosulfonic acid

Aminosulfonic acid

Sulphamic acid

Amidosulfuric acid

Imidosulfonic acid

Sulfamidic acid

Sulfaminic acid

Jumbo

Sulphamidic acid

Aminosulfuric acid

Kyselina sulfaminova

Kyselina amidosulfonova

sulfuramidic acid

NSC 1871

MFCD00011603

UNII-9NFU33906Q

amidohydroxidodioxidosulfur

H2NSO3H

Sulfamic acid, 99%

Caswell No. 809

Kyselina sulfaminova [Czech]

CAS-5329-14-6

HSDB 795

Kyselina amidosulfonova [Czech]

EINECS 226-218-8

UN2967

SULFAMIC ACID, ACS

EPA Pesticide Chemical Code 078101

SULFAMIC ACID, REAG

sulfoamine

Sulfamidsaeure

AI3-15024

Sulphamic-acid-

Amidoschwefelsaeure

amidosulphuric acid

sulfamic acid group

Sulfamic acid [UN2967] [Corrosive]

WLN: ZSWQ

sulfuric acid amide group

NH2SO3H

Sulfamic acid, ACS grade

ACMC-20a47z

NH3SO3

EC 226-218-8

NCIOpen2_000675

ARONIS25155

Molybdenum, Quant Test Strips

Sulfamic acid, p.a., 99.5%

Sulfamic acid, analytical standard

Sulfamic acid, reagent grade, 98%

7773-06-0 (mono-ammonium salt)

AKOS005287325

Sulfamic acid, ACS reagent, 99.3%

Sulfamic acid [UN2967] [Corrosive]

Sulfamic acid, ReagentPlus(R), >=99%

Sulfamic acid, >=99.5% (alkalimetric)

FT-0688102

Sulfamic acid, 99.999% trace metals basis

Sulfamic acid, SAJ first grade, >=99.0%

Sulfamic acid, JIS special grade, >=99.5%

Sulfamic acid, analytical standard (for acidimetry), ACS reagent

Sulfamic Acid is used as Descaler, Cleaner, Rust & Limescale Remover in industrial cleaning and maintaining applications.

Sulfamic acid is intended only for industrial applications, Sulfamic acid does not find consumer applications in pure form or as mixtures. 

Amidosulfonic Acid is used mainly in the chemical industry as an intermediate for chemical syntheses. 

Amidosulfonic Acid is also used in the textile industry, tanning, electroplating, paper making and metal refining.

Production of Sulfamic Acid :

The main methods for synthesizing sulfamic acids are by the sulfamation of alkyl amines with sulfur trioxide complexes R3N·SO3, and by treatment of amines with chlorosulfonic acid.

Properties of Sulphamic acid

Synonyms: sulfamic acid; Amidosulfonic acid; Amidosulphonic acid; sulphamidic acid;

CAS No: 5329-14-6

EINECS No: 226-218-8

Appearance: white crystalline solid

Molecular formula: NH2SO3H

Molar mass: 97.09 g/mol

Density: 2.15g/cm3

Solubility in water: 213 g/L (20C)

Melting point: 190 - 225 C

Boiling point: decomposes

pH: 1.2 (1% solution @ 20C)

Refractive index: 1.553

Sulfamic Acid

Applications

Cleaning agent:

Sulfamic acid is used as an acidic cleaning agent, sometimes pure or as a component of proprietary mixtures, typically for metals and ceramics. 

Sulfamic acid is frequently used for removingrust and limescale, replacing the more volatile and irritating hydrochloric acid, which is however cheaper. 

Sulfamic acid is often a component of household descaling agents, for example, Lime-A-Way Thick Gel contains up to 8% sulfamic acid and pH 2 - 2.2, or detergents used for removal of limescale. When compared to most of the common strong mineral acids, sulfamic acid has desirable water descaling properties, low volatility, low toxicity. It forms water-soluble salts of calcium and ferric iron.

​Importantly, sulfamic acid is preferable to use in household in comparison to hydrochloric acid for its intrinsic safety. 

If erroneously mixed with hypochlorite based products such as bleach, Sulfamic acid does not form chlorine gas, where the most common acids would; the reaction (neutralization) with NH3, produces a salt as depicted in the section above.

Sulfamic acid also finds applications in the industrial cleaning of dairy and brew-house equipment. 

Although Sulfamic acid is considered less corrosive than hydrochloric acid, corrosion inhibitors are often added to commercial cleansers of which it is a component. 

Some of its domestic use, e.g. Easy-Off, for descaling include home coffee and espresso equipment and in denture cleaners.

Other uses of Sulfamic Acid: 

​-Catalyst for esterification process

-Dye and pigment manufacturing

​-Herbicide

-Coagulator for urea-formaldehyde resins

-Ingredient in fire extinguishing media. Sulfamic acid is the main raw material for ammonium sulfamate which is a widely used herbicide and fire retardant material for household product.

-Pulp and paper industry as a chloride stabilizer

​-Synthesis of nitrous oxide by reaction with nitric acid

​-The deprotonated form (sulfamate) is a common counterion for nickel(II) in electroplating.

​-Silver polishing

USES OF SULPHAMIC ACID:

Descaler, Cleaner & Rust Remover

removing excess grout on tiles, efflorescence and other mineral deposits

Cleaner & descaler for Dairy equipment (pipeline milkers, milk evaporators)

Cleaner & descaler for Brewery equipment (pipelines, Vats, etc)

Catalyst for esterfication process process

Used in dye and pigment manufacture

Used as a herbicide

Effecticve against Foot and Mouth (approved bty Defra)

Ingredient in Denture Tablets

Coagulator for urea-formaldehyde resins

Ingredient in fire extinguishing media

Pulp and paper industry as a chloride stabilizer

Synthesis of nitrous oxide by reaction with nitric acid

Sulphamic acid in descaling

Sulfamic Acid is super efficient descaling agent and is used for cleaning a variety of industrial equipment and domestic appliances. It is used for cleaning boilers, heat exchangers, condensers, jackets and coils, descaling toilets, removing excess grout on tiles, efflorescence and other mineral deposits etc (See below for details on how to use). It helps remove hard water scale, protein deposits, beer and milk stone, light rust and copper corrosion

Sulphamic acid in paper & pulp Industry

Sulphamic Acid prevents pulp degradation due to temperature at the chlorination and hydrochloride stage. Sulfamic Acid permits bleaching at higher temperature and lower pH without loss of strength.

Sulphamic acid is used in manufacturing of Dyes, Pigments and in the dyeing of leather

Sulfamic Acid removes excess of nitrides used in the diazotization reactions in the manufacturing of dye stuffs and pigments. Nitrides if present in process water of effluents can also be removed by using Sulphamic Acid

Sulphamic acid in Chlorine Stabilization

Sulphamic Acid is used for stabilizing chlorine in swimming pools and cooling towers.

Sulphamic acid in Electroplating and Electro-refining

Sulfamic acid has been used in many organic preparations as a good solid catalyst. 

Sulphamic acid in Sulphation and Sulphamation

Sulfamic acid is used for sulphation and sulphamation of many organic compounds.

 

How to use Sulphamic Acid for cleaning & descaling:

For removing excess grout from tiling or dissolving efflorescence from walls, floors etc: Make up a solution of sulphamic acid by dissolving 80-100g per litre of warm water. Apply to surface using a cloth or brush and allow to work for a few minutes. Agitate with brush if necessary and rinse with clean water. Please Note: if using around coloured grout use a weaker solution of approx 2% (20g per litre of water) to reduce the risk of leaching out any colour from the grout.

For descaling equipment use a 10% solution. Sulphamic acid is safe for steel, iron, glass and wood equipment, and may be used with caution on copper, aluminium, and galvanized metal surfaces. Clean in a soak tank or by circulation. For surfaces, apply to surface using a cloth or brush and allow to work for a few minutes. Agitate with brush if necessary and rinse thoroughly with clean water.

For Boiler systems & Cooling Towers use a circulation treatment of a 10% to 15% solution depending on how bad the system is. Before applying flush out system and refill with clean water. Determine the volume of water and mix in the sulphamic acid at a rate of 100g to 150g per litre of water. It may be necessary to add a corrosion inhibitor to help protect mild steel, brass, copper and stainless steel from acid attack. Circulate the solution at room temperature or heated to a maximum of 60C for heavier cleaning for several hours until desired results are achieved. Note: Do not use at boiling point or product will undergo hydrolysis and will not work. Do not use on galvanised materials, zinc or aluminium. Sulphamic acid will not remove silica or calcium phosphate scales. After cleaning rinse thoroughly and check system. Neutralise with 1 to 2% sodium carbonate solution (soda ash) with a target pH of 6 to 8 or whatever discharge pH range applies.

Repeat applications may be necessary for heavily soiled systems. After cleaning Periodic flushing of the system to remove loosened scale and contaminants will be necessary.

For rust removal use a solution of 10%-20%.

Sulfamic acid NH2SO3H

Sulfamic acid has been one of the most widely used scavengers of nitrous acid. Sulfamic acid reacts to give nitrogen and bisulfate ion. 

Sulfamic acid has the advantage of a high solubility in water, for reactions carried out in water, and is often added as the ammonium salt. 

Sulfamic acid is a member of the following series of compounds: H2SO4 (sulfuric acid), H3NSO3 (sulfamic acid), H4N2SO2 (sulfamide), H5N3SO (unknown), and H6N4S (unknown).

Structure and reactivity

First, it should be noticed that the compound is well described by the formula H3NSO3, not the tautomer H2NSO2(OH). The relevant bond distances are S=O, 1.44 and S-N 1.77 Å. The greater length of the S-N distance is consistent with a single bond. Furthermore, a neutron diffraction study located the hydrogen atoms, all three of which are 1.03 Å distant from nitrogen. The structures shown with this article are for the two main tautomers.

Sulfamic acid is a weak acid, Ka = 1.01 x 10−1. Because the solid is non-hygroscopic, it is used as a standard in acidometry (quantitative assays of acid content). Double deprotonation can be effected in NH3 solution to give [HNSO3]2−.

Sulfamic acid melts at 205 °C before decomposing at higher temperatures to H2O, SO3, SO2, and N2.

With HNO2, sulfamic acid reacts to give N2, while with HNO3, it affords N2O.

The behavior of H3NSO3 resembles that of urea, (H2N)2CO, in some ways. Both feature amino groups linked to electron-withdrawing centers that can participate in delocalized bonding. Both liberate ammonia upon heating in water.

Applications

The most famous applicaton of sulfamic acid is in the synthesis of compounds that taste sweet. Reaction with cyclohexylamine followed by addition of NaOH gives C6H11NHSO3Na, sodium cyclamate. Related compounds are also sweeteners, see acesulfame potassium.

Sulfamates (O-substituted-, N-substituted-, or di-/tri-substituted derivatives of sulfamic acid) have been used in the design of many types of therapeutic agents such as antibiotics, nucleoside/nucleotide human immunodeficiency virus (HIV) reverse transcriptase inhibitors, HIV protease inhibitors (PIs), anti-cancer drugs (steroid sulfatase and carbonic anhydrase inhibitors), anti-epileptic drugs, and weight loss drugs.

Sulfamic acid is used as an acidic cleaning agent, typically for metals and ceramics. 

Sulfamic acid is a replacement for hydrochloric acid for the removal of rust. 

In households, Sulfamic acid is often found as a descaling agent in detergents used for removal of limescale.

USES OF SULFAMIC ACID :

Catalyst for esterification process

Dye and pigment manufacturing

Herbicide

Ingredient in Denture Tablets

Coagulator for urea-formaldehyde resins

Ingredient in fire extinguishing media

Pulp and paper industry as a chloride stabilizer

Synthesis of nitrous oxide by reaction with nitric acid

Sulfamic acid Benefits:

Sulfamic acid is technically advanced cleaner and descaler

Sulfamic acid contains a special film forming inhibitor

Sulfamic acid protects mild steel, stainless steel, copper and brass from acid attack

Sulfamic acid dissolves lime scale and other deposits

Sulfamic acid is ideal for boiler, calorifiers and heat exchangers

Preparation & Procedures

Sulphamic Acid should always be added to water, never add water to sulfamic acid.

At room temperature, diluted aqueous Sulphamic Acid is stable for a long period of time but hydrolysis occurs at elevated temperatures.

Concentrated sulfamic acid can be corrosive and can cause burns on the skin when it is not properly handled. This chemical is unique because it not only causes chemical burns, but also secondary thermal burns as a result of dehydration. It is vital to use proper PPE such as Rubber gloves, full clothing, rubber apron, and eye and face protection when mixing to avoid contact with unprotected skin. Contaminated clothing should be washed before being used again.

Health & Safety

R-phrase(s): R36/38 Irritating to eyes and skin. R52/53 Harmful to aquatic organisms, may cause long-term adverse effects in the aquatic environment.

S-phrase(s): S26 In case of contact with eyes, rinse immediately with plenty of water and seek medical advice. S28 After contact with skin, wash immediately with plenty of soap and water. S61 Avoid release to the environment. Refer to special instructions/ Safety data sheets.