SO3 Generator

For Industrial Applications

Produce SO3 gas online in small quantities

There is a wide range of application for gaseous SO3 in the industry. The strict conditions imposed by the EC in September 2017 on the use of hexavalent chromium (chrome VI) hit the industry hard and left many without a real solution for their process.

For decades, SO3 gas has been known to be an alternative to hexavalent chromium for surface treatment technology.
The process to win SO3 from oleum, however, has been complicated and dangerous to handle.


Pentol looks back at 50 years of experience in producing SO3 for large power stations. Recognizing the needs of the industry, Pentol has downsized SO3 generators small enough to be used in industrial processes. The SO3 generator is running fully automatic, providing a constant flow of SO3 in air gas available for your process.

The SO3 generator has been developed to comply with EC machinery directive and special emphasis has been put on SIL compliance, to allow an easy and safe integration into existing production plants.



The Pentol SO3 generator evaporates liquid SO2 from a gas bottle and dilutes it with compressed air. The mixture is heated and oxidized to SO3 by means of a catalyst. The SO3 generator is capable to process up to 150 l/h of SO2 in a mixture of max. 3 % SO2 in the air. The conversion rate to SO3 depends on the concentration and is higher than 70%.


A big emphasis has been put on the safety of the SO3 generator. SO3 by itself is very corrosive and needs to be handled with care.

The SO3 generator is equipped with a SOx sensor to detect leakages and shut down the process.


Continuous development on the SO3 generator is still in progress. With our demo unit, we collected enough of experience and information to produce the risk analysis and SIL analysis.

Based on these documents, we updated the design and are currently producing the first unit for a customer.


Final performance tests of this unit have been successful.
Orders will be accepted now.
Leave your email with us to be informed.

We need to get in touch personally.

Questions regarding function, support, and sales are answered via online chat support and e-mail to, as fast as possible.

As our continuous development on the SO3 generator is still in progress, we love to hear any suggestions and needs.


For more details download PDF

Related news