Chloroplatinic acid hexahydrate
CAS 18497-13-7
Chloroplatinic acid is the primary soluble platinum source of the industry — the precursor from which Pt/C and Pt/Al₂O₃ catalysts, hydrosilylation catalysts, plating baths and platinized electrodes are all made.
Typical specification
| Molecular formula | H₂PtCl₆ · 6H₂O |
|---|---|
| Molecular weight | 517.90 |
| Purity (metals basis) | ≥ 99.9% |
| Platinum content | ≥ 37.5% |
| Appearance | Orange-yellow to red-brown crystals |
| Base metals (Fe, Cu, Ni, Pb) | ≤ 50 ppm total, ICP per lot |
| Water solubility | Freely soluble; also soluble in ethanol, acetone |
| Available forms | Crystals or aqueous solution at specified Pt g/L |
| HS code (export) | 2843900039 |
Lot-specific COA issued with every shipment. SDS and ICP elemental impurity data available on request.
Where H₂PtCl₆·6H₂O is used
Hydrosilylation catalysis
Speier's catalyst (H₂PtCl₆ in isopropanol) and its derivatives cure silicone rubbers and functionalize silanes — the silicone industry's largest single use of platinum chemistry, feeding release coatings, LSR molding and electronic encapsulants.
Supported catalyst manufacture
The standard impregnation precursor for Pt/C, Pt/Al₂O₃ and bimetallic reforming and hydrogenation catalysts, where chloride content and Pt concentration control dispersion on the support.
Electroplating and electrode fabrication
Feeds platinum plating baths and the platinizing solutions used to prepare low-impedance electrodes for electrochemistry, sensors and electrolysis hardware.
Storage and shipping
Storage. Store tightly sealed in the original fluorinated or glass container; strongly hygroscopic and corrosive. Keep away from metals and reducing agents.
Shipping. Classified as corrosive (Class 8) for transport; shipped in UN-approved packaging with DG declaration. Solution grades available in DG-compliant carboys.
Packaging. 5 g · 25 g · 100 g · 500 g · Solution grades by contained Pt weight
Synonyms
- Hexachloroplatinic acid
- Dihydrogen hexachloroplatinate hexahydrate
- H2PtCl6
- Platinic chloride solution (as precursor)
- CPA
Frequently asked questions
Crystals or solution — which form should I buy?
Crystals store longer and ship at lower freight cost per gram of Pt; solutions at a certified Pt g/L save you a dissolution and assay step. High-volume catalyst and plating customers usually take solution on a standing schedule.
How is pricing quoted?
On contained platinum at the day's Pt fixing plus a conversion charge. The COA certifies exact Pt content per lot, so you pay for assayed metal, not nominal weight.
How do you handle the corrosive shipping classification?
We pack in UN-approved combination packaging with full DG documentation, and pre-clear the transport condition paperwork so air carriers accept the cargo without holds — typically adding two to three days versus non-DG freight.
Can platinum-bearing residues be returned for credit?
Yes — spent plating baths, filter residues and off-spec solutions are assayed and the platinum credited at the agreed fixing against future supply.