Product

Refined LPG, also known as sweetened LPG, is a commercially traded liquefied petroleum gas that has undergone a purification process—most commonly Merox or similar sweetening technology—to remove sulfur compounds and other contaminants. This process reduces hydrogen sulfide and mercaptan concentrations to very low levels, producing an LPG product that is odorless (apart from any added odorant for leak detection), non-corrosive, and compliant with strict regulatory and market specifications required for use in domestic, industrial, and automotive applications. The sweetening process (e.g., Merox) primarily removes sulfur compounds but may be paired with hydrotreating if significant olefins are present and product specification demands are stringent.

Refined LPG is produced from both petroleum refining and natural gas processing. Its constituents are mainly propane, butane and iso-butane and mixtures of these gases. In standard commercial LPG, the olefin content is typically very low or negligible. Only in certain industrial applications or geographic regions might “unsweetened” or partially hydrogenated LPG streams retain measurable butylenes and propylene. The composition of commercial LPG can vary by country—using propane, butane, or blends—according to local standards (for example, LPG in Australia is primarily propane).

Refined vs. Raw LPG Constituents

Chemical Data

LPG remains liquid under moderate pressure but becomes gaseous at atmospheric pressure and temperature, allowing for safe storage and transport in steel vessels ranging from small gas bottles to large bulk storage tanks.

Notes

• All data above refer specifically to refined (sweetened) LPG, after treatment to remove sulfur and other impurities, meeting domestic and commercial product standards.
• Properties depend on the ratio of propane, butane, and other light hydrocarbons as per local or national regulations.
• Sulfur is reduced to strict specifications: in many markets, <5 ppm by mass, commonly as ≤0.001 wt% in the final product.

References

1. UOP. "Merox™ Process for LPG Sweetening." Honeywell UOP Brochure, 2022.
2. National Fire Protection Association (NFPA) 58, Liquefied Petroleum Gas Code (product purity requirements), 2024.
3. U.S. Department of Energy – Clean Cities Alternative Fuel Data Center – LPG Propane
4. ELGAS, 30 Oct 2022, LPG Properties & LPG Composition –  What Are the Properties of LPG