Potassium Fluoborate Potassium Tetrafluoroborate · KBF₄
The white crystalline fluoroborate salt used in aluminium and magnesium metallurgy, brazing and soldering fluxes, and resin-bonded abrasives. A natural partner to our master alloys and grain refiner tablets.
Chelora Chemicals delivers potassium fluoborate to foundries, flux makers and abrasive manufacturers across the United States, with a batch COA and SDS on every consignment.
- CAS Number
- 14075-53-7
- EC Number
- 237-928-2
- IUPAC name
- Potassium tetrafluoroborate
- Molecular formula
- KBF₄
- Molecular weight
- 125.90 g/mol
- Melting point
- ≈ 530 °C
- Density
- ≈ 2.5 g/cm³
- HS Code
- 2826 90
Note: KBF₄ is moisture sensitive — keep containers sealed and dry. Confirm exact hazard and transport classification on the SDS for your batch.
From fluoroborate to refined aluminium
Potassium fluoborate feeds boron-bearing master alloys and metal-treatment products. The stages below are products on this site.
Related fluorides and fluxes: potassium fluoride · sodium silicofluoride · cover flux
What KBF₄ is used for
Potassium fluoborate (potassium tetrafluoroborate, KBF₄) is a white to light-grey crystalline powder, only slightly soluble in water and sensitive to moisture. It is made by reacting fluoroboric acid with a potassium base, after which the KBF₄ crystallises, is separated, washed and dried.
Its main industrial uses are as a flux and additive in aluminium and magnesium metallurgy, as a raw material for boron-containing alloys, as a component of brazing and soldering fluxes, and as an active filler in resin-bonded grinding wheels. It also appears in tin and tin-lead electroplating baths and as a fluoride source in synthesis.
Where it fits
- Aluminium & magnesium. Flux and refining aid, and raw material for boron alloys used in casting.
- Brazing & soldering. Ingredient in flux formulations for joining metals.
- Abrasives. Filler in resin-bonded grinding wheels.
- Plating & synthesis. Tin and tin-lead plating baths, and a fluoride-ion source.
Handling character
KBF₄ is moisture sensitive and is classed on many SDS as an irritant to skin, eyes and the respiratory tract, with some SDS classing it as corrosive. Full hazard detail is in the Safety section below.
| Parameter | Value |
|---|---|
| Appearance | White to light-grey crystalline powder |
| Purity (KBF₄) | Per grade; commonly traded at 98% and 99% min |
| Moisture | Per batch COA |
| Particle size | Per grade, stated on COA |
| Free acidity / insolubles | Per batch COA |
Important: the grades above are indicative of commercial material and are offered for planning only. The batch certificate of analysis is the governing document.
| Property | Value |
|---|---|
| Physical state | White crystalline powder, odourless |
| Melting point | ≈ 530 °C |
| Density | ≈ 2.5 g/cm³ |
| Water solubility | ≈ 4.4 g/L at 20 °C |
| Stability | Moisture sensitive; incompatible with strong oxidisers |
Physical constants compiled from public reference data for CAS 14075-53-7 and rounded for readability. Treat them as orientation, not as a specification.
Where our customers put KBF₄ to work
From aluminium and magnesium casting to brazing fluxes and abrasives.
Aluminium & magnesium metallurgy
Flux and refining aid in melts, and raw material for boron-containing alloys used in casting.
Brazing & soldering fluxes
An ingredient in flux formulations for joining metals.
- Flux-maker supply
- Granulated flux
Resin-bonded abrasives
Used as an active filler in resin-bonded grinding wheels.
- Powder grades by particle size
- Documented batch traceability
Electroplating
A component in tin and tin-lead plating baths.
- Process-scale quantities
- Full documentation supplied
Fluoride & fine chemicals
A fluoride-ion source in synthesis and catalyst preparation.
Contract & scheduled supply
Plants running continuous consumption are supported with scheduled delivery against a call-off calendar.
- Annual contracts with scheduled call-off
- Price held across the contract period
Delivered to US plants and ports
We ship Potassium Fluoborate to nominated delivery points across the United States. Chelora Chemicals is a sourcing and supply partner, not a US manufacturer, and does not hold US stock.
Gulf Coast
Entry point for bulk and containerised consignments.
- Houston & Galveston, TX
- New Orleans & Baton Rouge, LA
Northeast
Delivery into the mid-Atlantic and New England manufacturing belt.
- Newark & Elizabeth, NJ
- Philadelphia, PA
Southeast
Port-side delivery for Carolinas, Georgia and Florida plants.
- Savannah, GA
- Charleston, SC
Midwest & Great Lakes
Rail and truck forwarding to the industrial Midwest.
- Chicago, IL
- Detroit, MI
- Cleveland & Columbus, OH
West Coast
Pacific routing for West Coast die casters and foundries.
- Los Angeles & Long Beach, CA
- Seattle & Tacoma, WA
Southwest & Mountain
Inland delivery forwarded from the Gulf or Pacific gateway.
- Dallas–Fort Worth, TX
- Phoenix, AZ
- Denver, CO
Importing into the United States
Potassium fluoborate is a TSCA-regulated chemical substance, and public references list it on the TSCA Inventory. Under TSCA section 13 the importer of record, or its authorised agent, must certify to US Customs and Border Protection that each shipment either complies with TSCA or is not subject to it. We confirm the substance's Inventory status and agree in writing who files that certification before the first consignment moves.
Which party carries that duty follows the Incoterm. On FOB, CFR or CIF terms it is usually the US buyer; on DDP terms it can be the seller or its agent. Safety data sheets and labels are supplied to OSHA's updated Hazard Communication Standard, and transport classification is confirmed before booking.
| Item | How it works |
|---|---|
| Delivery points | Any nominated US plant, warehouse or port of discharge |
| Incoterms quoted | FOB · CFR · CIF · DDP |
| Importer of record | Agreed in writing before the first shipment |
| TSCA certification | Section 13 certification filed at entry |
| Documentation | Batch COA, SDS, packing list, certificate of origin |
| Pack formats | Bags, FIBC or drums, confirmed at quotation |
Note: regional coverage describes where we deliver, not where we hold inventory. Lead time depends on producer scheduling and ocean transit to your nominated US port — we confirm both in the quotation.
How we supply potassium fluoborate
Chelora Chemicals is a supplier and sourcing partner, not a manufacturer. Purity, moisture and particle size decide whether a lot suits a flux, a melt or a grinding wheel, which shapes how we select producers on this line.
We place your order with whichever qualified producer best matches your grade, price point and delivery window, and confirm US import requirements before booking.
- Grade confirmed before we quote. Purity, moisture and particle size are checked against your process, not just the headline assay.
- TSCA status and import certification settled first. We confirm Inventory status and agree who files the section 13 certification before the first shipment.
- Hazard and transport documents checked. Classification is taken from the batch SDS and confirmed before booking.
- Batch traceability to the producing plant. Full chain of custody documentation on request.
- One desk for the melt shop. Order alongside master alloys, cover flux and potassium fluoride.
Sealed against moisture
KBF₄ is moisture sensitive, so we quote lined, sealed packs. Tell us your preferred format and we will classify to it.
Lined bags
PP-woven or multi-wall bags with a polyethylene inner liner to hold back moisture. Bag size confirmed at quotation.
Liner-fitted jumbo bags
Bulk bags for plants handling material by hoist or bag-tip station.
Sealed drums
Rigid, stackable packs where your warehouse and handling route suit them.
Incoterms to suit you
Quoted on the Incoterm your purchasing team works to, with documentation filed before booking.
Trial / sample quantities
Small packs dispatched for process qualification before a commercial order is placed.
Irritant, moisture sensitive — keep it dry
Potassium fluoborate is an irritant powder that is toxic by ingestion and sensitive to moisture. The summary below is orientation only — the safety data sheet supplied with your specific batch is the authoritative document.
Commonly listed hazards
H315Causes skin irritation.H319Causes serious eye irritation.H335May cause respiratory irritation.
Classification varies. Some suppliers classify KBF₄ more strictly, as causing severe skin burns and eye damage (H314), and some references list it as toxic if swallowed. Treat the powder as corrosive and follow the SDS for your batch.
Storage
Store in tightly closed containers in a cool, dry, well-ventilated area, away from moisture, strong oxidisers and metals. Keep bags sealed between uses.
Handling
Handle with local exhaust ventilation and dust control. Avoid inhaling dust, wear eye protection, gloves and protective clothing, and keep washings out of drains.
Transport
Some references list KBF₄ under UN 3260, Corrosive solid, acidic, inorganic, n.o.s. We confirm and document the exact classification and routing for your specific shipment and destination from the SDS.
Every batch, documented
We verify documentation before dispatch so there are no surprises at your incoming-goods bench.
Specification agreed
Purity, moisture and particle size confirmed against your process requirement before order placement.
Producer batch testing
The producing plant tests each batch against the agreed specification before release.
Documentation review
COA, SDS, TSCA certification data and transport paperwork checked by our desk before the shipment is booked.
Traceable dispatch
Each shipment is traceable to its producing batch, with full chain-of-custody records on request.
How KBF₄ is made
Potassium fluoborate is made from fluoroboric acid, which is formed by reacting hydrofluoric acid with boric acid. The acid is then neutralised with a potassium base such as potassium hydroxide or potassium carbonate, and the KBF₄ precipitates as crystals.
The crystals are separated by centrifuge, washed and dried. Because KBF₄ is only slightly soluble in water, it drops out of solution cleanly, which is why purity and moisture depend on washing and drying. Its fluoride content also makes it a relative of potassium fluoride and sodium silicofluoride.
We do not publish operating process parameters here; this is background only. Full technical documentation accompanies every shipment, and any process-specific detail you need is best confirmed directly with our technical desk.
| Chemical family | Inorganic fluoroborate salt |
|---|---|
| Synonyms | Potassium tetrafluoroborate, potassium borofluoride, KBF₄ |
| Reactivity | Moisture sensitive; incompatible with strong oxidisers |
| Related fluorides | Potassium fluoride, sodium silicofluoride |
| Downstream | Master alloys, fluxes, abrasives |
The rest of the fluoride and foundry range
Related fluorides, alloy additives and fluxes, all supplied from the same desk.
Potassium fluoborate, answered
What is potassium fluoborate used for?
What is the difference between potassium fluoborate and potassium tetrafluoroborate?
What is the CAS number and formula?
Is potassium fluoborate hazardous?
Is KBF4 soluble in water?
What grade and purity do you supply?
What packing do you offer?
Do you supply potassium fluoborate in the United States?
Who is the importer of record for US shipments, and what documents come with it?
Do you manufacture this yourself?
Get a quote on Potassium Fluoborate
Send us your required grade, pack size, US delivery point and Incoterm. We will come back with a firm quote, lead time and full documentation, and can price related fluorides and foundry products in the same enquiry.