This is an old revision of the document!
- chemical precipitation using iron hydroxide.
For precision desulphurization, impregnated or doted activated carbon is normally used (catalytic oxidation and following adsorption).
Alternatively, chemisorption on iron oxide- or hydroxide-coated materials in an external column can be applied for precision desulphurization. Chemisorption using zinc oxide in external columns is basically also applicable, but currently not state-of-the-art for precision desulphurization of biogas.
The six most widespread technologies are
- pressure swing adsorption,
- water scrubber,
- physical absorption (using organic solvents),
- chemical absorption (using organic solvents),
- high-pressure membrane separation and
- cryogenic upgrading.