- Contact us -
- Print this page - - Send to a friend -
  • Oil Refining
  • Petrochemicals
  • Gases
  • Alternative Fuels
  • Water


SweetSulf™ is a redox process developed for high pressure natural gas applications. Its specific solid sulfur removal technology overcomes the foaming/plugging problems experienced with other types of redox processes. SweetSulf™ has been demonstrated on an industrial pilot plant operated with natural gas under 80 bar, at a Engie underground storage facility.

Process Scheme

Process Principle

  • Reaction: Sour Gas is contacted with an aqueous redox solution which extracts the H2S and converts it into solid elemental sulfur.
  • Gas separation: Treated gas, free of H2S, is separated from the redox solution.
  • Solid separation: Solid sulfur is filtered under pressure on a cartridge filter which can be regenerated on stream.
  • Re-Oxidation The redox solution is depressurized and re-oxidized by contact with air.


  • SweetSulf™ process has been proven for high pressure operation with 6 760 hours of industrial pilot operation
  • SweetSulf™ can treat any composition of gas in the range of H₂S concentration below 5 000 ppm
  • H₂S outlet levels can go below 1 ppm
  • Economic application range 10 – 1 000 ppm H₂S in feed
  • CO₂ partial pressure limited to # 4 bar

Key Benefits

  • Selective H2S removal with direct conversion into solid elemental sulfur
  • gas sweetening may be done at any pressure
  • Ambient temperature operation
  • High Pressure Filtration: no foaming, no risk of plugging
  • Flexibility, easy operation
  • Minimum solvent flowrates and pumping costs
  • CAPEX and total costs can be 20 – 50% lower than for conventional processes for feed H2S levels between 10 and 1 000 ppm)

Associated Offer

Catalysts & Adsorbents



Axens Horizon
Axens Horizon
Operations Support

Modular Offer & Equipment