Gases
Ultra-high-purity acetylene — 99.99 %, dissolved in DMF, for atomic absorption spectroscopy
Ultra-high-purity acetylene is dissolved in DMF rather than acetone and refined to 99.99 % C₂H₂, with phosphine and hydrogen sulphide each below 10 ppm. Those two impurities are what disturb the flame in atomic absorption spectroscopy. KIGL is one of very few manufacturers in India producing this grade, in dedicated DMF cylinders, batch-verified.
₹1,200 – ₹2,200 per Nm³ Indicative. Your quotation is the figure that counts — price moves with quantity, cylinder size, contract term and delivery.
- 99.99 % C₂H₂
- Purity
- DMF
- Solvent
- < 10 ppm
- Phosphine (PH₃)
- < 10 ppm
- Hydrogen sulphide (H₂S)
- Dedicated DMF-charged
- Cylinder type
The grade that exists for one reason
Most acetylene is bought to melt metal. This grade is bought to not interfere with a measurement.
In atomic absorption spectroscopy, the acetylene flame is part of the instrument. Anything the gas carries into that flame — phosphine, hydrogen sulphide, solvent vapour — becomes background signal, baseline drift and a worse detection limit. At trace concentrations the gas quality stops being a consumable and becomes part of the analytical error budget.
KIGL manufactures ultra-high-purity acetylene at 99.99 % C₂H₂, dissolved in DMF, with phosphine and hydrogen sulphide each below 10 ppm. Industrial acetylene can carry phosphine in the hundreds of ppm. That is the difference this product exists to deliver.
Why the solvent is the whole story
Acetylene cannot be stored on its own as free compressed gas; it decomposes. It is compressed into solution in a solvent held inside a porous mass. Which solvent you choose determines what the gas is good for.
Acetone is standard for industrial dissolved acetylene. It works, it is cheap, and its relatively high vapour pressure means a meaningful quantity of acetone leaves the cylinder along with the gas. For cutting steel this is irrelevant. For a flame you are measuring through, it is not.
DMF has a substantially lower vapour pressure. Far less solvent is carried over, the delivered gas is cleaner and steadier, and the cylinder holds a better ratio of gas to solvent. It costs more and demands dedicated cylinders that never see acetone.
We run DMF filling as a separate, dedicated operation for exactly this reason.
Specification
The impurity limits below are what matter for analytical work. Read them before the purity figure.
See the specification table for full values: 99.99 % C₂H₂, PH₃ < 10 ppm, H₂S < 10 ppm, batch-verified with a certificate of analysis.
The cylinder filling manifold — one header, one gauge, many cylinders
Guwahati works · agent network
Who uses it
Analytical laboratories running flame AAS for trace metals; environmental and water-testing laboratories; materials and metallurgical laboratories; academic and research institutions; and quality-control laboratories in pharmaceuticals, food and mining.
If your work is cutting, welding, brazing or flame heating, you want industrial dissolved acetylene instead. This grade would be an expensive way to melt steel.
Availability
Supplied in dedicated DMF cylinders from our filling operations, with a certificate of analysis per batch. Because the cylinders are dedicated and the filling is a separate operation, lead times differ from industrial DA. Talk to us about your consumption and we will set up a schedule.
Why KIGL
Why this is rare in India
Producing this grade commercially needs three things at once: a purification train that can hold phosphine and hydrogen sulphide to single-digit ppm, a dedicated DMF filling operation with cylinders that never cross-contaminate, and batch analysis to prove it. Most Indian acetylene producers have none of them, and imports carry long lead times and heavy dangerous-goods freight costs.
KIGL has made acetylene since 1947 and builds its own acetylene plants. The purification capability that makes this grade possible is our own engineering, not a bought-in package.
Specification
Ultra-high-purity acetylene — full specification
| Property | Value | Basis |
|---|---|---|
| Purity | 99.99 % v/v | Batch analysis |
| Solvent | DMF (N,N-dimethylformamide) | KIGL product specification |
| Phosphine (PH₃) | < 10 ppm | Batch analysis |
| Hydrogen sulphide (H₂S) | < 10 ppm | Batch analysis |
| Cylinder type | Dedicated DMF-charged, porous mass | KIGL product specification |
| Primary application | Atomic absorption spectroscopy (AAS) | — |
| Chemical formula | C₂H₂ | — |
| Cylinder charge | Porous mass, DMF-charged, dedicated service | IS 7312 cylinder construction |
| Batch documentation | Certificate of analysis per batch | — |
Documents
Ultra-high-purity acetylene — safety and technical documentation
Questions
Ultra-high-purity acetylene — frequently asked questions
Why DMF instead of acetone for high-purity acetylene?
DMF has a much lower vapour pressure than acetone, so far less solvent leaves the cylinder with the gas. In atomic absorption spectroscopy, solvent carry-over shows up directly as baseline noise and drift. DMF also permits a higher gas-to-solvent ratio, giving more usable gas per cylinder at a steadier delivery.
Why do phosphine and hydrogen sulphide matter so much in AAS?
They disturb the flame and contribute background signal, which is exactly what degrades detection limits at trace concentrations. Industrial acetylene can carry phosphine in the hundreds of ppm; ours is held below 10 ppm. For trace metals work that difference determines whether a result is usable.
Can I run UHP acetylene in a cylinder that previously held industrial DA?
No. The cylinders are dedicated. An acetone-charged cylinder will contaminate DMF-grade gas, and the two solvents must never be mixed. UHP acetylene is supplied only in its own dedicated cylinders.
How is 99.99 % achievable when industrial acetylene is 98 %?
By solvent and by purification, not by wishful specification. Industrial dissolved acetylene sits in acetone and carries phosphine and hydrogen sulphide through from the calcium carbide. The ultra-high-purity grade uses DMF, is purified to strip those contaminants, and is filled into dedicated cylinders that never see industrial service. Each batch is verified and ships with a certificate of analysis — ask for it, and check it against this page.
Do you provide a certificate of analysis?
Yes. Each batch is verified and documented. Ask at the time of order if your laboratory accreditation requires the certificate to accompany delivery.
Which instruments is this grade suitable for?
Any air-acetylene or nitrous oxide-acetylene flame AAS instrument. It also suits flame photometry and other applications where flame stability and low background matter.
Read next
Enquiries
Request a quotation for ultra-high-purity acetylene
State the gas or equipment, the quantity or capacity, and your location. KIGL will confirm the grade, the cylinder or plant size, and whether the location can be served from Noonmati, or through our agent network.