Potassium Ferrocyanide Trihydrate: Uses, Grades and Sourcing

What is Potassium Ferrocyanide used for? Mainly as an analytical and process chemical. Uses include detecting iron, precipitating metals, making Prussian Blue pigments, serving as an electrochemical redox standard, and deicing. Allan Chemical lists Potassium Ferrocyanide in ACS and Technical grades on the Potassium Ferrocyanide 3H₂O product page.

What Potassium Ferrocyanide is, and what the compound is not

In the [Fe(CN)₆]⁴⁻ ion, six cyanide groups are bound to Fe(II) in a very stable complex. The trihydrate forms lemon-yellow crystals or a yellowish-white powder. The cyanide is bound inside the iron complex rather than present as free cyanide ion.

Where Potassium Ferrocyanide is used

Metal detection and titration. Iron(III) plus ferrocyanide gives intense Prussian Blue. Zinc can be titrated with ferrocyanide.

Electrochemistry. The ferrocyanide/ferricyanide couple is reversible and well behaved, at about +0.36 V versus the standard hydrogen electrode, which makes the couple a common test probe for cyclic voltammetry and electrode checks.

Pigments and photography. Prussian Blue is made by combining ferrocyanide with iron(III) salts. Uses also include iron-based photographic processes.

Deicing. Uses include deicing.

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Key properties

The names and identifiers in this table match the PubChem compound record. For the material you receive, the Safety Data Sheet (SDS) and lot Certificate of Analysis (COA) are the documents to rely on.

Hydration state matters

The two forms differ by about 13% in molecular weight, so purchase orders that name the trihydrate and CAS 14459-95-1 keep specifications aligned from quote to delivery.

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Which grade of Potassium Ferrocyanide fits which application?

What buyers often confirm before ordering

• Hydration state: trihydrate, CAS 14459-95-1.
• Grade: ACS or Technical, matched to the process.
• Lot COA and SDS: current versions for the product received.
• Packaging: typically plastic drums.

Allan Chemical has supplied specialty chemicals since 1984 and is International Organization for Standardization (ISO) 9001:2015 certified. Material arrives in sealed original containers, not repackaged by Allan Chemical, so the lot number on the label stays matched to the lot COA. See how to read a COA and why lot traceability matters.

What is the difference between ferrocyanide and ferricyanide?

The two are easy to confuse and are not interchangeable. Potassium Ferrocyanide is K₄[Fe(CN)₆] with iron(II) and forms yellow crystals. Potassium Ferricyanide, K₃[Fe(CN)₆] (CAS 13746-66-2), contains iron(III), appears red and acts as an oxidizing agent. The two give different colors with metal ions (ferrocyanide with Fe³⁺ gives Prussian Blue; ferricyanide with Fe²⁺ gives Turnbull’s Blue, a similar deep blue), so checking the label and CAS number on the container is a good habit before using either as a test reagent.

Frequently Asked Questions

Is Potassium Ferrocyanide the same as cyanide?

No. Potassium Ferrocyanide is a separate compound in which the cyanide groups are bound to iron(II) in a very stable complex.

What are other names for Potassium Ferrocyanide?

Potassium Hexacyanoferrate(II) and Yellow Prussiate of Potash. The trihydrate is CAS 14459-95-1.

Which grade fits a titration or a process application?

ACS grade for titrations, analytical reagents and electrochemistry; technical grade for industrial and process use. Matching the grade to the method and reading the lot COA against the grade’s specification keeps results consistent.

What molecular weight applies to the trihydrate?

422.39 g/mol. The anhydrous salt is 368.35 g/mol, so confirming the hydration state on the label and the COA keeps calculations aligned.

Which grades of Potassium Ferrocyanide does Allan Chemical list?

ACS and Technical, typically in plastic drums. The product page shows the current grades and sizes.

Why buy Potassium Ferrocyanide from Allan Chemical?

Allan Chemical has supplied specialty chemicals since 1984, is ISO 9001:2015 certified, and ships sealed original containers without repackaging, so the lot number on the label stays matched to the lot COA. Contact Us for a quote.

References

Allan Chemical resources

1. Allan Chemical: Potassium Ferrocyanide 3H₂O
2. What Is a Certificate of Analysis (COA)?

External sources

1. PubChem: Potassium Ferrocyanide compound summary

This article is for general information and sourcing guidance. Please consult the current official product specification and a qualified professional for your specific application.