SULFAMIC ACID

CAS No.: 5329-14-6
EC No.: 226-218-8

Synonyms:
SULFAMIC ACID; sulfamic acid; SÜLFAMİK ASİT; sülfamik asit; SULFAMIC ACID; 5329-14-6; Amidosulfonic acid; Aminosulfonic acid; Sulfamic acid; Amidosulfuric acid; Imidosulfonic acid; Sulfamidic acid; Sulfaminic acid; Jumbo; Sulphamidic acid; Aminosulfuric acid; Kyselina sulfaminova; Kyselina amidosulfonova; Caswell No. 809; sulfuramidic acid; NSC 1871; MFCD00011603; Kyselina sulfaminova [Czech]; UNII-9NFU33906Q; HSDB 795; Kyselina amidosulfonova [Czech]; amidohydroxidodioxidosulfur; SULFAMIC ACID; sulfamic acid; SÜLFAMİK ASİT; sülfamik asit; SULFAMIC ACID; sulfamic acid; SÜLFAMİK ASİT; sülfamik asit; EINECS 226-218-8; H2NSO3H; UN2967; EPA Pesticide Chemical Code 078101; CHEMBL68253; AI3-15024; CHEBI:9330; [S(NH2)O2(OH)]; 9NFU33906Q; Sulfamic acid [UN2967] [Corrosive]; Sulfamic acid, 99%; DSSTox_CID_14005; SULFAMIC ACID; sulfamic acid; SÜLFAMİK ASİT; sülfamik asit; SULFAMIC ACID; sulfamic acid; SÜLFAMİK ASİT; sülfamik asit; DSSTox_RID_79107; DSSTox_GSID_34005; CAS-5329-14-6; SULFAMIC ACID, ACS; SULFAMIC ACID, REAG; sulfoamine; Sulfamidsaeure; Sulphamic-acid-; Amidoschwefelsaeure; amidosulphuric acid; sulfamic acid group; WLN: ZSWQ; sulfuric acid amide group; NH2SO3H; Sulfamic acid, ACS grade; ACMC-20a47z; NH3SO3; EC 226-218-8; NCIOpen2_000675; KSC269M4H; ARONIS25155; Molybdenum, Quant Test Strips; DTXSID6034005; BDBM26994; CTK1G9643; NSC1871; Sulfamic acid, p.a., 99.5%; Sulfamic acid, analytical standard; [N]S(O)(=O)=O; NS([O])(=O)=O; KS-000000UE; NSC-1871; SULFAMIC ACID; sulfamic acid; SÜLFAMİK ASİT; sülfamik asit; Sulfamic acid, reagent grade, 98%; Tox21_201905; Tox21_303482; 8894AF; ANW-56397; STL282725; 7773-06-0 (mono-ammonium salt); AKOS005287325; Sulfamic acid, ACS reagent, 99.3%; ZINC238809066; MCULE-8047713803; UN 2967; KS-0000472G; NCGC00090927-01; NCGC00090927-02; SULFAMIC ACID; sulfamic acid; SÜLFAMİK ASİT; sülfamik asit; SULFAMIC ACID; sulfamic acid; SÜLFAMİK ASİT; sülfamik asit; NCGC00257489-01; NCGC00259454-01; Sulfamic acid [UN2967] [Corrosive]; Sulfamic acid, ReagentPlus(R), >=99%; Sulfamic acid, >=99.5% (alkalimetric); SULFAMIC ACID; sulfamic acid; SÜLFAMİK ASİT; sülfamik asit; LS-147664; FT-0688102; Sulfamic acid, 99.999% trace metals basis; Sulfamic acid, SAJ first grade, >=99.0%; Sulfamic acid, JIS special grade, >=99.5%; Q412304; W-105754; Sulfamic acid, analytical standard (for acidimetry), ACS reagent; 226-218-8 [EINECS]; 5329-14-6 [RN]; SULFAMIC ACID; sulfamic acid; SÜLFAMİK ASİT; sülfamik asit; Acide sulfamique [French] [ACD/IUPAC Name]; amidosulfonic acid; Amidosulfuric acid; aminosulfonic acid; Imidosulfuric acid [ACD/Index Name]; Kyselina amidosulfonova [Czech]; Kyselina sulfaminova [Czech]; SULFAMIC ACID; sulfamic acid; SÜLFAMİK ASİT; sülfamik asit; MFCD00011603 [MDL number]; Sulfamic acid [ACD/Index Name] [ACD/IUPAC Name]; sulfamidic acid; Sulfamidsäure [German] [ACD/IUPAC Name]; [5329-14-6]; 7773-06-0 (Mono-ammonium salt); 99.99% (metals basis); amidohydroxidodioxidosulfur; SULFAMIC ACID; sulfamic acid; SÜLFAMİK ASİT; sülfamik asit; Amidoschwefelsaeure; Amidosulfonicacid; Aminosulfuric acid; Imidosulfonic acid; Kyselina amidosulfonova [Czech]; Kyselina sulfaminova [Czech]; SULFAMIC ACID; sulfamic acid; SÜLFAMİK ASİT; sülfamik asit; SO2 [Formula]; Sulfamic acid [UN2967] [Corrosive]; Sulfamic acid, acs; Sulfamic acid, ACS grade; Sulfamic acid, reag; Sulfamidsaeure; SULFAMIC ACID; sulfamic acid; SÜLFAMİK ASİT; sülfamik asit; Sulfaminic acid; SULFITE ION; sulfuramidic acid; SULPHAMIC ACID; Sulphamic-acid-; SULFAMIC ACID; sulfamic acid; SÜLFAMİK ASİT; sülfamik asit; Sulphamidic acid; UN 2967; WLN: ZSWQ; 氨基磺酸 [Chinese]; SULFAMIC ACID; sulfamic acid; SÜLFAMİK ASİT; sülfamik asit; SULFAMIC ACID; sulfamic acid; SÜLFAMİK ASİT; sülfamik asit; SULFAMIC ACID; 5329-14-6; Amidosulfonic acid; Aminosulfonic acid; Sulfamic acid; Amidosulfuric acid; Imidosulfonic acid; Sulfamidic acid; Sulfaminic acid; Jumbo; Sulphamidic acid; Aminosulfuric acid; Kyselina sulfaminova; Kyselina amidosulfonova; Caswell No. 809; sulfuramidic acid; NSC 1871; MFCD00011603; Kyselina sulfaminova [Czech]; UNII-9NFU33906Q; HSDB 795; Kyselina amidosulfonova [Czech]; amidohydroxidodioxidosulfur; SULFAMIC ACID; sulfamic acid; SÜLFAMİK ASİT; sülfamik asit; SULFAMIC ACID; sulfamic acid; SÜLFAMİK ASİT; sülfamik asit; EINECS 226-218-8; H2NSO3H; UN2967; EPA Pesticide Chemical Code 078101; CHEMBL68253; AI3-15024; CHEBI:9330; [S(NH2)O2(OH)]; 9NFU33906Q; Sulfamic acid [UN2967] [Corrosive]; Sulfamic acid, 99%; DSSTox_CID_14005; SULFAMIC ACID; sulfamic acid; SÜLFAMİK ASİT; sülfamik asit; SULFAMIC ACID; sulfamic acid; SÜLFAMİK ASİT; sülfamik asit; DSSTox_RID_79107; DSSTox_GSID_34005; CAS-5329-14-6; SULFAMIC ACID, ACS; SULFAMIC ACID, REAG; sulfoamine; Sulfamidsaeure; Sulphamic-acid-; Amidoschwefelsaeure; amidosulphuric acid; sulfamic acid group; WLN: ZSWQ; sulfuric acid amide group; NH2SO3H; Sulfamic acid, ACS grade; ACMC-20a47z; NH3SO3; EC 226-218-8; NCIOpen2_000675; KSC269M4H; ARONIS25155; Molybdenum, Quant Test Strips; DTXSID6034005; BDBM26994; CTK1G9643; NSC1871; Sulfamic acid, p.a., 99.5%; Sulfamic acid, analytical standard; [N]S(O)(=O)=O; NS([O])(=O)=O; KS-000000UE; NSC-1871; SULFAMIC ACID; sulfamic acid; SÜLFAMİK ASİT; sülfamik asit; Sulfamic acid, reagent grade, 98%; Tox21_201905; Tox21_303482; 8894AF; ANW-56397; STL282725; 7773-06-0 (mono-ammonium salt); AKOS005287325; Sulfamic acid, ACS reagent, 99.3%; ZINC238809066; MCULE-8047713803; UN 2967; KS-0000472G; NCGC00090927-01; NCGC00090927-02; SULFAMIC ACID; sulfamic acid; SÜLFAMİK ASİT; sülfamik asit; SULFAMIC ACID; sulfamic acid; SÜLFAMİK ASİT; sülfamik asit; NCGC00257489-01; NCGC00259454-01; Sulfamic acid [UN2967] [Corrosive]; Sulfamic acid, ReagentPlus(R), >=99%; Sulfamic acid, >=99.5% (alkalimetric); SULFAMIC ACID; sulfamic acid; SÜLFAMİK ASİT; sülfamik asit; LS-147664; FT-0688102; Sulfamic acid, 99.999% trace metals basis; Sulfamic acid, SAJ first grade, >=99.0%; Sulfamic acid, JIS special grade, >=99.5%; Q412304; W-105754; Sulfamic acid, analytical standard (for acidimetry), ACS reagent; 226-218-8 [EINECS]; 5329-14-6 [RN]; SULFAMIC ACID; sulfamic acid; SÜLFAMİK ASİT; sülfamik asit; Acide sulfamique [French] [ACD/IUPAC Name]; amidosulfonic acid; Amidosulfuric acid; aminosulfonic acid; Imidosulfuric acid [ACD/Index Name]; Kyselina amidosulfonova [Czech]; Kyselina sulfaminova [Czech]; SULFAMIC ACID; sulfamic acid; SÜLFAMİK ASİT; sülfamik asit; MFCD00011603 [MDL number]; Sulfamic acid [ACD/Index Name] [ACD/IUPAC Name]; sulfamidic acid; Sulfamidsäure [German] [ACD/IUPAC Name]; [5329-14-6]; 7773-06-0 (Mono-ammonium salt); 99.99% (metals basis); amidohydroxidodioxidosulfur; SULFAMIC ACID; sulfamic acid; SÜLFAMİK ASİT; sülfamik asit; Amidoschwefelsaeure; Amidosulfonicacid; Aminosulfuric acid; Imidosulfonic acid; Kyselina amidosulfonova [Czech]; Kyselina sulfaminova [Czech]; SULFAMIC ACID; sulfamic acid; SÜLFAMİK ASİT; sülfamik asit; SO2 [Formula]; Sulfamic acid [UN2967] [Corrosive]; Sulfamic acid, acs; Sulfamic acid, ACS grade; Sulfamic acid, reag; Sulfamidsaeure; SULFAMIC ACID; sulfamic acid; SÜLFAMİK ASİT; sülfamik asit; Sulfaminic acid; SULFITE ION; sulfuramidic acid; SULPHAMIC ACID; Sulphamic-acid-; SULFAMIC ACID; sulfamic acid; SÜLFAMİK ASİT; sülfamik asit; Sulphamidic acid; UN 2967; WLN: ZSWQ; 氨基磺酸 [Chinese]; SULFAMIC ACID; sulfamic acid; SÜLFAMİK ASİT; sülfamik asit

SULFAMIC ACID

Sulfamic acid
Infobox references
Sulfamic acid, also known as amidosulfonic acid, amidosulfuric acid, aminosulfonic acid, and sulfamidic acid, is a molecular compound with the formula H3NSO3. This colourless, water-soluble compound finds many applications. Sulfamic acid melts at 205 °C before decomposing at higher temperatures to water, sulfur trioxide, sulfur dioxide and nitrogen.

Sulfamic acid (H3NSO3) may be considered an intermediate compound between sulfuric acid (H2SO4), and sulfamide (H4N2SO2), effectively replacing a hydroxyl (–OH) group with an amine (–NH2) group at each step. This pattern can extend no further in either direction without breaking down the sulfonyl (–SO2–) moiety. Sulfamates are derivatives of sulfamic acid.

Production
Sulfamic acid is produced industrially by treating urea with a mixture of sulfur trioxide and sulfuric acid (or oleum). The conversion is conducted in two stages:

OC(NH2)2 + SO3 → OC(NH2)(NHSO3H)
OC(NH2)(NHSO3H) + H2SO4 → CO2 + 2 H3NSO3
In this way, approximately 96,000 tonnes were produced in 1995.

Structure and reactivity

Ball-and-stick model of a sulfamic acid zwitterion as it occurs in the crystal state.
The compound is well described by the formula H3NSO3, not the tautomer H2NSO2(OH). The relevant bond distances are 1.44 Å for the S=O and 1.77 Å for the S–N. The greater length of the S–N 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 the nitrogen.In the solid state, the molecule of sulfamic acid is well described by a zwitterionic form.

Aqueous solutions of sulfamic acid are unstable and slowly hydrolyse to ammonium bisulfate, but the crystalline solid is indefinitely stable under ordinary storage conditions. Its behaviour resembles that of urea, (H2N)2CO. Both feature amino groups linked to electron-withdrawing centres that can participate in delocalised bonding. Both liberate ammonia upon heating in water ; however, the sulfamic acid reverts back to sulfuric acid , in place of the CO2 that urea would release , according to the following reaction :

H3NSO3 + H2O → H2SO4 + NH3
Acid–base reactions
Sulfamic acid is a moderately strong acid, Ka = 0.101 (pKa = 0.995). Because the solid is not hygroscopic, it is used as a standard in acidimetry (quantitative assays of acid content).

H3NSO3 + NaOH → NaH2NSO3 + H2O
Double deprotonation can be effected in ammonia solution to give the anion HNSO2−
3.

H3NSO3 + 2 NH3 → HNSO2−
3 + 2 NH+
4
Reaction with nitric and nitrous acids
With nitrous acid, sulfamic acid reacts to give nitrogen:

HNO2 + H3NSO3 → H2SO4 + N2 + H2O
while with nitric acid, it affords nitrous oxide:

HNO3 + H3NSO3 → H2SO4 + N2O + H2O
Reaction with hypochlorite
The reaction of excess hypochlorite ions with sulfamic acid or a sulfamate salt gives rise reversibly to both N-chlorosulfamate and N,N-dichlorosulfamate ions.

HClO + H2NSO3H → ClNHSO3H + H2O
HClO + ClNHSO3H ⇌ Cl2NSO3H + H2O
Consequently, sulfamic acid is used as hypochlorite scavenger in the oxidation of aldehydes with chlorite such as the Pinnick oxidation.

Reaction with alcohol
Upon heating sulfamic acid will react with alcohols to form the corresponding organosulfates. It is more expensive than other reagents for doing this, such as chlorosulfonic acid or oleum, but is also significantly milder and will not sulfonate aromatic rings. Products are produced as their ammonium salts. Such reactions can be catalyzed by the presence of urea.

ROH + H2NSO3H → ROS(O)2O− + NH+
4
Without the presence of any catalysts , sulfamic acid will not react with ethanol at temperatures below 100 °C .

Applications
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, such as 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), anticancer drugs (steroid sulfatase and carbonic anhydrase inhibitors), antiepileptic drugs, and weight loss drugs.

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. It is frequently used for removing rust and limescale, replacing the more volatile and irritating hydrochloric acid, which is cheaper. It is often a component of household descaling agents, for example, Lime-A-Way Thick Gel contains up to 8% sulfamic acid and has pH 2.0–2.2,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, and low toxicity. It forms water-soluble salts of calcium and ferric iron.

Sulfamic acid is preferable to hydrochloric acid in household use, due to its intrinsic safety. If erroneously mixed with hypochlorite based products such as bleach, it does not form chlorine gas, whereas the most common acids would; the reaction (neutralisation) with ammonia, produces a salt, as depicted in the section above.

It also finds applications in the industrial cleaning of dairy and brewhouse equipment. Although it is considered less corrosive than hydrochloric acid, corrosion inhibitors are often added to the commercial cleansers of which it is a component. It can be used for descaling home coffee and espresso machines and in denture cleaners.

Other uses
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 products.
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.
Used to separate nitrite ions from mixture of nitrite and nitrate ions( NO3−+ NO2−) during qualitative analysis of nitrate by Brown Ring test.
Silver polishing
According to the label on the consumer product, the liquid silver cleaning product TarnX contains thiourea, a detergent, and sulfamic acid.

Description
General description
Sulfamic acid (H2NSO3H) is widely used inorganic compound. It exists in zwitterionic form and neutral forms. Zwitterionic form has been reported to be is more stable than neutral form. Its industrial applications have been reported.It has various organic synthesis applications.

Sulfamic acid is a strong inorganic acid. It is a hypochlorite scavenger.The ability of sulfamic acid to reduce nitrate to nitrogen gas under acidic condition has been utilized to denitrify nitrate-rich wastewater along with zinc powder.

Application
Sulfamic acid (H2NSO3H) may be used in the following studies:
• As catalyst in the synthesis of aryl-14H-dibenzo[a.j]xanthenes.
• As green catalyst for the preparation of amide from ketoxime.
• As ammonia equivalent in the regioselective synthesis of primary allylic amines, via allylic substitution reactions.
• Synthesis of polysubstituted quinolones.
Sulfamic acid may be used in the following processes:
• As a titrant in the determination of the burette injection volume and chemical calibration factor.
• To neutralize excess nitrous acid in the colorimetric paracetamol assay by modified Glynn and Kendal colorimetric method.
• To prevent endogenous mercury (Hg) loss during the urine Hg measurement by inductively coupled plasma mass spectrometry (ICP-MS) method.
• As an acid catalyst and a hypochlorite scavenger in the chlorite oxidation of dialdehyde cellulose (DAC).
• As a heterogeneous catalyst in the synthesis of polyhydroquinoline derivatives by Hantzsch condensation reaction.
• As catalyst in the degradation of bamboo fiber to 5-hydroxymethylfurfural (HMF).
• As an acid reagent in the determination of silicates in water samples based on centrifugal microfluidics.
• As catalyst in the synthesis of deazaoxaflavin at room temperature.

2.06.3.9 Sulfamic Acid and Derivatives Thereof: R1NHSO3R2, R12NSO3R2
The general synthetic methods used for the preparation of sulfamic acids were reviewed in COFGT (1995) <1995COFGT(2)333>.

2.06.3.9.1 Sulfamic acids: R12NSO3H
Ring opening of cyclic sulfamidates by acylamines or thiols results in the formation of sulfamic acid salts (Equation (39)) <2003OL811>. This process has been used in a synthesis of thiomorpholine and piperazine derivatives. Antibacterial agents <2000T5571> and oligosaccharide derivatives <2003OBC2253> are among recently described biologically active compounds containing sulfamic acids.

Bicyclic sulfamate 83 readily reacts with lithium diphenylphosphide to generate sulfamic acid 84 in excellent yields (Scheme 8). Hydrolysis of this reaction intermediate under oxygen free conditions eventually leads to the formation phosphine ligand 85.120 Compound 83 undergoes a similar reaction in the presence of lithiated benzene derivatives. Acidic hydrolysis of sulfamic acid intermediates at high temperature furnishes substituted 2-benzyl pyrrolidines 87 in a stereocontrolled fashion (Scheme 8).44 Ring-opening of bicyclic sulfamates can also be achieved by treatment with the sodium salt of 2-chloro-5-hydroxypyridine to form racemic pyridyl ethers.43

N-sulfoglucosamine (CHEBI:21794) has functional parent sulfamic acid (CHEBI:9330)
N-sulfotyrosine (CHEBI:90373) has functional parent sulfamic acid (CHEBI:9330)
cyclohexylsulfamic acid (CHEBI:15964) has functional parent sulfamic acid (CHEBI:9330)
phaseolotoxin (CHEBI:8047) has functional parent sulfamic acid (CHEBI:9330)
sulfamate ester (CHEBI:48199) has functional parent sulfamic acid (CHEBI:9330)
sulfamoyl group (CHEBI:48266) is substituent group from sulfamic acid (CHEBI:9330)

Sulfamic Acids; R2NSO3H
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 . For example, the sulfamic acid of 5′-amino-5′-deoxyadenosine was prepared by treatment of 5′-amino-5′-deoxyadenosine with Me3N·SO3 in anhydrous methanol   A number of other preparative methods for sulfamic acids have been reported, for example the treatment of isocyanates or urethanes with oleum , and the reaction of hydroxylamines or amine N-oxides with sulfur dioxide . Catechol sulfate reacts with amines to give 2-(hydroxyphenyl) sulfamate esters, which can be hydrolyzed to yield potassium salts of sulfamic acids . A large number of heterocyclic sodium sulfamates, het-NHSO3−Na+, have been prepared for testing as artificial sweeteners . Of interest, although not part of this chapter, the N-acylsulfamate monobactam antibiotics are β-lactams with a sulfamate moiety on the β-lactam nitrogen, and are normally prepared using sulfur trioxide complexes.

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

advantage of a high solubility in water, for reactions carried out in water, and is often added as the ammonium salt. Kinetic measurements at 0°C and later at 25°C show that there is acid catalysis up to ~0.2 M, thereafter the rate constant is independent of acidity. The results are interpreted in terms of reaction via the sulfamate ion NH2SO3−, and the two sets of results yield values of 0.98 and 1.1 for the pKa of sulfamic acid (literature value 1.0). This means that sulfamic acid is a better nitrous acid trap at low acidities (typically 0.05 M) than is either hydrazine of hydrazoic acid, but is less good at higher acidities. There is no nucleophilic catalysis, so the sulfamate ion behaves more like an amide than an amine, in which there is a rate-limiting proton transfer from the rapidly formed N-nitroso intermediate. The kinetic isotope effect, kH/kD of 2.7 supports this sequence, 

Sulfamic acids: R12NSO3H
Ring opening of cyclic sulfamidates by acylamines or thiols results in the formation of sulfamic acid salts (Equation (39)) <2003OL811>. This process has been used in a synthesis of thiomorpholine and piperazine derivatives. Antibacterial agents <2000T5571> and oligosaccharide derivatives <2003OBC2253> are among recently described biologically active compounds containing sulfamic acids.

Sulfamic Acid: A Cleaning Agent Used in Various Industries
Sulfamic acid is a white crystalline solid which is non-hygroscopic and stable. Sulfamic acid is a super-efficient agent for descaling. It is used for cleaning a number of domestic appliances and industrial equipment. Sulfamic acid is used as an acidic cleaning agent, usually for ceramics and metals. Sulfamic acid is a safe and powerful acid, which is suitable for descaling applications and acid cleaning.

Sulfamic acid also called as amido sulfuric acid is a white crystalline solid which is non-hygroscopic and stable. It is soluble in formamide and water, and slightly soluble in concentrated sulfuric acid, methanol, acetone, and ether. It is commercially produced from fuming sulfuric acid and urea, and classified as a strong inorganic acid. The sulfamic acid with dilute aqueous solution is stable for longer periods at room temperature. However, a rapid hydrolysis arises at high temperatures. The sulfamic acid is considered as less corrosive to metals compared to other strong acid such as hydrochloric acid. As the sulfamic acid retains a scale solubilizing capacity it is considered ideal for removal of scale from cooling towers, boilers, coils, condensers, heat exchangers and a wide range of cooling and heating systems thereby amassing the efficiency of equipment and plant.

Uses of Sulfamic Acid

As sulfamic acid is super-efficient agent for descaling, it is used for cleaning a number of domestic appliances and industrial equipment. It is used for cleaning heat exchangers, boilers, condensers, descaling toilets, jackets and coils, efflorescence other deposits of mineral deposits, removing excess grout on tiles, etc. It helps remove protein deposits, hard water scale, beer and milk stone, copper corrosion, and light rust. Some other uses of sulfamic acids are listed below.

•    Descaler, rust remover, and cleaner.
•    Descaler and cleaner for dairy equipment such as milk evaporators, milkers’ pipeline.
•    Descaler and cleaner for brewery equipment such as vats, pipelines, etc.
•    Catalyst for esterification process.
•    Used in dye & pigment manufacturing
•    Used as an herbicide.
•    Effective against foot and mouth.
•    Used as an ingredient in denture tablets.
•    Ingredient in fire extinguishing media.
•    Urea-formaldehyde resins coagulator
•    Synthesis of nitrous oxide by reaction with nitric acid.
•    Chloride stabilizer in pulp & paper industry.

Sulfamic Acid as a Cleaning Agent

As per Research Dive analyst review, sulfamic acid is used as an acidic cleaning agent, usually for ceramics and metals. Over the last few years sulfamic acid has replaced hydrochloric acid as a remover of the rust. In homes, it is frequently found as a descaling agent in toilet cleaners, and detergents for the removing the lime scale. When compared to other strong and most common strong mineral acids, the sulfamic acid has the needed low toxicity, low volatility, and water descaling properties. It forms water-soluble salts of ferric iron and calcium.

Sulfamic acid provides intrinsic safety and hence it is preferred over hydrochloric acid for household use. Unlike the most common acids, the sulfamic acid does not form chlorine gas if invalidly mixed with hypochlorite based products.

Industrial Applications of Sulfamic Acid

The sulfamates have been used in the design of various types of therapeutic agents such as nucleotide/nucleoside HIV, antibiotics, HIV protease inhibitors (PIs), weight loss drugs, antiepileptic drugs, and anticancer drugs. Sulfamic acid is also used as a chlorine stabilizer in cooling towers and swimming pools. The industrial applications of sulfamic acid are as follows:

Paper & pulp Industry

Sulfamic Acid inhibits pulp degradation due to temperature at the hydrochloride and chlorination stage. It allows bleaching at elevated temperature and lower pH without any loss in strength.

Dyes & Pigments Industry

Sulfamic acid takes out excess of nitrides that are used in the diazotization reactions during the manufacturing of pigments and dye stuffs. The sulfamic acid can also remove nitrides if present in process water of emissions.

Conclusion

Sulfamic acid is a safe and powerful acid, which is suitable for descaling applications and acid cleaning. One of the most common use of sulfamic acid is for descaling heating coils and heated vessels in the food handling premises owing to its ability to quickly dissolve hardness deposits without objectionable odors or fumes. Hence, sulfamic acid is considered as the most popular, safe, preferred acid in various industries.

Sulfamic Acid
Applications

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.

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. It is frequently used for removingrust and limescale, replacing the more volatile and irritating hydrochloric acid, which is however cheaper. It 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, it 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 called sulfamic acid is a white crystalline solid which is stable and non-hygroscopic. It is soluble in water and formamide and slightly soluble in methanol, ether, acetone and concentrated sulphuric acid. It 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.

Sulfamic 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

Sulfamic acid in paper & pulp Industry

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

Sulfamic 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

Sulfamic acid in Chlorine Stabilization
Sulphamic Acid is used for stabilizing chlorine in swimming pools and cooling towers.
Sulfamic acid in Electroplating and Electro-refining
Sulfamic 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. Sulfamic 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. Sulfamic 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%.