In short: All three treat odors and low-concentration VOCs, but differently. UV photocatalytic units break molecules with 253.7 / 185 nm light, ozone and a TiO₂ catalyst (design removal up to 99%). Low-temperature plasma breaks bonds with energetic electrons while the gas stays near ambient. Activated carbon captures organics on the carbon surface and suits low-concentration, high-flow or intermittent exhaust, but needs replacement or regeneration.
Side by side
| UV photocatalytic | Low-temperature plasma | Activated carbon | |
|---|---|---|---|
| Principle | 253.7 nm UV breaks bonds; 185 nm makes ozone; TiO₂ catalyst | High-voltage discharge; energetic electrons and radicals | Adsorption on carbon surface |
| Typical targets | NH₃, H₂S, mercaptans, trimethylamine, CS₂, styrene | Odors and organics from pharma, rubber, ink, feed, refinery, wastewater | Low-level, high-flow or intermittent VOCs |
| Catalog performance | Design odor removal up to 99% | Per project data | Per carbon load and contact time |
| Consumables | UV lamps | Electrodes / power | Carbon replacement or regeneration |
| Construction | SUS304 modular housing, pre-filter | Modular units | SUS304, carbon steel or PP; FRP shell for corrosive gas |
UV photocatalytic oxidation
253.7 nm UV breaks the bonds of ammonia, trimethylamine, hydrogen sulfide, methyl mercaptan, carbon disulfide, styrene and similar compounds; 185 nm UV splits oxygen to form ozone, which oxidizes the fragments to CO₂ and water. The honeycomb catalyst carrier increases the lamp effect 10–30 times according to the catalog.
Low-temperature plasma
A high-voltage discharge creates energetic electrons and reactive radicals that break odor and VOC molecules while the gas stays near ambient temperature.
Activated carbon adsorption
Gas is pretreated (cooling, dust and mist removal), then passes through drawer, horizontal or cylindrical beds of columnar, honeycomb or fiber carbon. It suits low-concentration, high-flow or intermittent high-concentration exhaust. Carbon must be replaced or regenerated when saturated.
When a biofilter is better
For steady, biodegradable odors such as wastewater H₂S and ammonia, bio-deodorization units run with low consumables: catalog design values are empty-bed residence time ≥20 s, gas velocity ≤0.1 m/s, media depth 1–2 m and 20–35 °C. For higher VOC concentrations, see the RTO vs RCO vs zeolite rotor guide.
All three units are in VOC and odor treatment units.
Watch: UV vs Plasma vs Carbon in 27 Seconds
FAQ
Can the technologies be combined?
Yes. UV or plasma followed by activated carbon is a common combination; units can be supplied alone or together.
What data do you need?
Air flow, odor or VOC species and concentrations, temperature, humidity, dust and the outlet target.
Values in this guide are catalog design and selection references. Final sizes, laminate and performance are confirmed in writing in the quotation for your operating data.
Related guides
Next step: Send air flow, pollutants and outlet target. Send it through our quote form and we will reply with a sized proposal.