SO3
Sulfur trioxide · Sulfuric anhydride
Sulfur trioxide is a stable, insulating oxide of sulfur that functions as the primary industrial precursor for the manufacturing of sulfuric acid.
About Sulfur trioxide
Sulfur trioxide is a highly reactive inorganic compound that exists as a wide-gap insulating oxide. As a thermodynamically stable phase, it occupies a significant position in chemical synthesis, particularly due to its role as the primary precursor for large-scale industrial acid production. Its structural versatility is evidenced by the numerous reported configurations across major materials databases. This compound is essential for manufacturing processes that require strong dehydrating agents and chemical intermediates. Its ability to act as a potent Lewis acid makes it indispensable in the synthesis of various sulfonated organic compounds and industrial detergents.
Key Properties
Cross-validated computational properties for Sulfur trioxide, aggregated across 4 databases.
Band GapEnergy needed to move an electron from the valence band to the conduction band. Lower or zero values tend to behave more metallic; larger gaps are more insulating or semiconducting.
Energy Above HullThermodynamic distance from the most stable set of competing phases. 0 eV/atom is on the convex hull; small positive values may still be experimentally accessible.
StabilityA plain-language summary of the best reported energy-above-hull result. It reflects whether the lowest-energy structure is on, near, or far from the stability hull.
StructuresCount of reported calculated crystal structures for this formula, including alternate polymorphs, source databases, and observed space groups.
Synthesis Routes
Literature-extracted synthesis procedures targeting SO3.
Applications
Where Sulfur trioxide is used.
Patent Landscape
21 patents reference SO3 or close compositional variants.
| Patent | Title | Assignee | Granted |
|---|---|---|---|
| 3950493 | Process for absorbing SO.sub.3 | — | — |
| 4548789 | Mono-stage device to generate gaseous SO.sub.3 from melted sulphur | — | — |
| 4419423 | Nonaqueous cells employing heat-treated MnO.sub.2 cathodes and a PC-DME-LiCF.sub.3 SO.sub.3 electrolyte | — | — |
| 4766104 | Process for producing a V.sub.2 O.sub.5 -and-alkali-metal-sulfate-containing catalyst for oxidizing SO.sub.2 t | — | — |
| 4304759 | Process for obtaining metal oxide and SO.sub.2 -containing gases essentially free of SO.sub.3 and H.sub.2 SO.s | — | — |
| 9487401 | Process for the oxidation of SO2 to SO3 | — | — |
| 5387402 | Contact reactor for a quasi-isothermal catalytic oxidation of SO.sub.2 to SO.sub.3 and method of operating sam | — | — |
| 4331632 | Catalytic cartridge SO.sub.3 decomposer | — | — |
| 8980497 | Secondary battery including anode with a coating containing a SO3 containing compound | — | — |
| 6500402 | Catalyst for oxidizing SO2 to SO3 and utilization of the catalyst in a method for producing sulfuric acid | — | — |
Frequently Asked Questions
Common questions about Sulfur trioxide, answered from cross-validated data.
What is SO3?
Sulfur trioxide is a stable, insulating oxide of sulfur that functions as the primary industrial precursor for the manufacturing of sulfuric acid.
What is SO3 used for?
What is the band gap of SO3?
Is SO3 a metal, semiconductor, or insulator?
Is SO3 thermodynamically stable?
How many polymorphs of SO3 are known?
How is SO3 synthesized?
What elements does SO3 contain?
Where does the data for SO3 come from?
How It Compares
As a fundamental inorganic oxide, sulfur trioxide stands as a critical reference point for sulfur-based chemistry. Unlike many transient or metastable oxides, its position on the thermodynamic convex hull ensures its reliability as a chemical building block in industrial applications.
Data sources & attribution
- latticegraph — Lattice Graph Materials Intelligence Platform
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