Nickel sulfamate (13770-89-3) Physical and Chemical Properties
Nickel sulfamate
A water‑soluble nickel(II) salt commonly supplied as aqueous solutions for use as a plating electrolyte and nickel source in electroforming and surface treatment for industrial and R&D applications.
| CAS Number | 13770-89-3 |
| Family | Nickel salts (inorganic) |
| Typical Form | Aqueous solution (liquid) |
| Common Grades | EP, Reagent Grade, USP |
Nickel sulfamate is an inorganic nickel(II) salt of the sulfamate (sulfamidate) anion and belongs to the class of water‑soluble metal sulfamates. Structurally it is best described as nickel(II) coordinated to two sulfamate anions (formally sulfamic acid deprotonated), giving an overall neutral compound with the formula H4N2NiO6S2. Electronically, the material contains a d8 Ni(II) center that is stabilized by the anionic, oxygen‑ and nitrogen‑containing sulfamate ligands; the ligand set provides multiple hydrogen‑bond acceptor sites and substantial polar surface area, consistent with high aqueous solubility and strong coordination ability. The supplied structural descriptors include SMILES "NS(=O)(=O)[O-].NS(=O)(=O)[O-].[Ni+2]" and InChIKey KERTUBUCQCSNJU-UHFFFAOYSA-L.
As a nickel(II) salt of an anionic amidosulfonate, nickel sulfamate exhibits class‑typical behavior: it is highly polar, forms stable aqueous solutions, and displays Lewis‑acidic metal behaviour with pH‑dependent hydrolysis and ligand‑exchange chemistry. Solutions are not lipophilic and are dominated by ionic speciation; hydrolysis of Ni(II) at elevated pH and complexation by chelating ligands or anions are important determinants of speciation. Industrially and commercially, nickel sulfamate is widely used in nickel electroplating and electroforming processes where soluble Ni(II) is required; aqueous solutions sold for these purposes are commonly supplied at defined nickel concentrations.
Common commercial grades reported for this substance include: EP, Reagent Grade, USP.
Basic Physical Properties
Density
No experimentally established value for this property is available in the current data context.
Melting or Decomposition Point
No experimentally established value for this property is available in the current data context.
Solubility in Water
Nickel sulfamate is water‑soluble and is supplied commercially as aqueous solutions (examples in trade supply include concentrated formulations). Representative product forms reported include a 50% aqueous solution described as a blue‑green liquid and solutions specified by nickel content (commercial solutions reported containing approximately 11% nickel). Solubility is governed by ionic dissociation of the Ni(II) cation and the sulfamate anion and by concentration‑dependent speciation.
Solution pH (Qualitative Behavior)
Aqueous solutions of nickel sulfamate are typically mildly acidic to near‑neutral depending on concentration and counterion balance because Ni(II) undergoes limited hydrolysis and the sulfamate ligand is the conjugate base of a strongish amidosulfonic acid. Solution pH will vary with concentration and any added acid or base, and technical baths used in plating are commonly adjusted to a target pH to control deposition kinetics and speciation.
Chemical Properties
Acid–Base Behavior
The sulfamate anion is the deprotonated form of sulfamic acid; in salt form it acts as a non‑complexing or weakly coordinating anion relative to harder ligands but still offers oxygen and nitrogen donor sites for secondary coordination and hydrogen bonding. Nickel(II) behaves as a borderline Lewis acid: in aqueous media it can undergo hydrolysis to form hydroxide species at elevated pH and readily participates in ligand exchange and complex formation with chelators (e.g., amines, phosphines, carboxylates). Protonation–deprotonation of the sulfamate ligand is not typically significant in strongly basic environments because the anion is already deprotonated in the salt.
Reactivity and Stability
Nickel sulfamate is generally stable in aqueous solution under normal laboratory and industrial conditions. It is susceptible to typical metal‑salt reactions: ligand exchange with stronger coordinating ligands, precipitation of nickel hydroxide at high pH, and complexation by chelating agents. The compound should be considered reactive toward strong reducing or oxidizing agents only in the sense that redox chemistry involving nickel can occur under forcing conditions; Ni(II) is relatively stable but can be involved in redox processes in the presence of appropriate reagents. Thermal decomposition data are not provided here; for thermal or long‑term stability concerns, product‑specific technical literature or material safety documentation should be consulted.
Molecular and Ionic Parameters
Formula and Molecular Weight
- Molecular formula: H4N2NiO6S2
- Molecular weight: 250.87 \(\mathrm{g}\,\mathrm{mol}^{-1}\)
Additional computed parameters available for the covalently‑represented unit and ionic components include exact/monoisotopic mass 249.886420 and topological polar surface area 183 (computed descriptors reflect the high polarity and multiple H‑bond acceptor sites).
Constituent Ions
- Cation: nickel(II), \( \mathrm{Ni}^{2+} \)
- Anion(s): two sulfamate (sulfamidate) anions (derived from sulfamic acid, often written as \(\mathrm{NH_2SO_3^-}\) or sulfamidate)
The supplied SMILES string represents the disconnected ionic components: NS(=O)(=O)[O-].NS(=O)(=O)[O-].[Ni+2], indicating a salt composed of a divalent nickel cation and two monovalent sulfamate anions.
Identifiers and Synonyms
Registry Numbers and Codes
- CAS number: 13770-89-3
- EC number: 237-396-1
- InChI: InChI=1S/2H3NO3S.Ni/c21-5(2,3)4;/h2(H3,1,2,3,4);/q;;+2/p-2
- InChIKey: KERTUBUCQCSNJU-UHFFFAOYSA-L
- SMILES: NS(=O)(=O)[O-].NS(=O)(=O)[O-].[Ni+2]
- DSSTox Substance ID: DTXSID2065622
- Wikidata: Q10373228
(Deprecated or related registry identifiers reported in technical listings include 5329-14-6 as a related parent CAS and 1333123-32-2 as a deprecated CAS.)
Synonyms and Common Names
Common synonyms and alternate names reported for this substance include:
- Nickel sulfamate
- Nickel(II) sulfamate
- Sulfamic acid, nickel(2+) salt (2:1)
- nickel(2+) disulfamate
- Nickel sulphamate
- Nickel sulfamic acid
- nickel bis(sulfamidate)
- Nickel (II) sulfamate
Commercial product designations and catalog synonyms (vendor labels) may include additional trade strings; the above are the principal systematic and common names encountered in technical contexts.
Industrial and Commercial Applications
Functional Roles and Use Sectors
Nickel sulfamate is principally used as a soluble source of nickel(II) for electrochemical metal deposition. Its primary industrial role is as a plating and electroforming agent where soluble Ni(II) must be supplied in a controlled, reproducible form. Reported industry uses include plating agents and surface‑treating agents for electrical equipment, appliance components, and other manufactured parts requiring nickel finishes. Production and commercial activity for sulfamic‑acid nickel salts have been documented in large‑scale manufacturing sectors.
Reported aggregated U.S. commercial volumes (examples of production reporting) include: 2019: 2,771,294 lb; 2018: 3,509,404 lb; 2017: 2,957,124 lb; 2016: 1,950,057 lb.
Typical Application Examples
- Nickel electroforming baths and nickel electroplating formulations.
- Surface treating agents where a dissolved Ni(II) source is required.
- Laboratory reagent for nickel chemistry and materials research where a non‑sulfate, amidosulfonate counterion is desired.
If a concise product selection is required, users choose nickel sulfamate when strong aqueous solubility, predictable ionic speciation, and compatibility with plating bath chemistries are priorities.
Safety and Handling Overview
Health and Environmental Hazards
Nickel sulfamate and soluble nickel(II) compounds present significant health hazards typical of soluble nickel salts. Key hazard attributes reported include:
- Acute toxicity by ingestion and inhalation (classified in hazard categories for acute toxicity).
- Skin and respiratory sensitization potential; can cause allergic contact dermatitis and occupational asthma in sensitized individuals.
- Carcinogenicity: nickel compounds have classifications indicating carcinogenic potential by inhalation and are associated with increased lung and nasal‑sinus cancer risk in occupational exposure settings.
- Reproductive and developmental toxicity concerns have been reported for certain nickel compounds.
- Specific target organ toxicity on repeated exposure, with respiratory system effects prominently reported.
- Very toxic to aquatic life with long‑lasting effects.
Selected hazard and precaution codes reported in technical classifications include H302, H317, H332, H334, H341, H350/H350i, H360D, H372, H400, and H410 (these represent acute toxicity, sensitization, mutagenicity, carcinogenicity, reproductive toxicity, organ toxicity on repeated exposure, and aquatic hazards). Reported occupational exposure limits include a permissible exposure limit (PEL) of \(1.0\,\mathrm{mg}\,\mathrm{m}^{-3}\) (as Ni), an IDLH of \(10.0\,\mathrm{mg}\,\mathrm{m}^{-3}\) (as Ni), and a threshold limit value (TLV) of \(0.1\,\mathrm{mg}\,\mathrm{m}^{-3}\) (inhalable fraction, as Ni). Routes of exposure of concern include inhalation, dermal contact, and ingestion.
For workplace control, measures to prevent inhalation and dermal contact are essential; medical surveillance and exposure monitoring are appropriate in industrial settings where nickel compounds are handled.
Storage and Handling Considerations
- Store in tightly closed containers in a cool, well‑ventilated area away from incompatible materials (strong oxidizers/reducers) and foodstuffs.
- Use engineering controls to minimize airborne dust or aerosols; employ local exhaust ventilation for processing and transfer operations.
- Personal protective equipment should include suitable gloves, eye/face protection, and respiratory protection when airborne exposures cannot be otherwise controlled.
- Avoid release to the environment; soluble nickel compounds can pose significant aquatic toxicity risks and must be managed to prevent uncontrolled discharge.
- For detailed hazard, transport and regulatory information and for product‑specific handling and emergency measures, users should refer to the product‑specific Safety Data Sheet (SDS) and local legislation.
