Iron oxide desulfurizes Biogas

Bayoxide® E16 offers a highly effective, easy to meter and absolutely sustainable way to remove hydrogen sulfide from Biogas

Biogas is gaining in popularity because it is an ecological, resource-conserving and climate-neutral energy source.


In a biogas plant, organic substances are decomposed and fermented under anaerobic conditions, meaning in the absence of oxygen. These systems process crops, liquid waste from livestock such as slurry, agro-industrial residues and bio-waste from commercial businesses and households. Fermentation produces a gas comprised chiefly of methane, which in most cases is used directly on site to power a generator. Depending on the starting materials, biogas contains fluctuating levels of hydrogen sulfide, on average about 500 milligrams per cubic meter. The hydrogen sulfide must be removed from the gas because of its toxicity, odor and, above all, the corrosive effect of the sulfur compounds on the fermentation reactor and generator. Furthermore, without desulfurization, the catalytic converter used to process generator exhaust gases may be ineffective and result in formaldehyde values which exceed accepted limits.


With Bayoxide® E 16 LANXESS offers a highly effective synthetic iron oxide hydroxide for reducing hydrogen sulfide in biogas. It is based on the globally occurring natural mineral goethite and can be added directly to the fermentation reactor. Bayoxide® E 16 reacts with hydrogen sulfide to form iron sulfide and sulfur, which – in line with the German fertilizer regulation – as substances occurring naturally in soil can be used to fertilize fields, together with the fermentation residue. 

Because the product is added in its unopened sack, metering is simple and dust-free.


Using the new Bayoxide® E 16 product offers numerous advantages. For instance, it helps to avoid the corrosion damage often caused by sulfuric acid formation, which otherwise occurs if the common ‘air supply’ method is used to remove the hydrogen sulfide. What is more, no danger exists of explosive mixtures of methane and atmospheric oxygen forming due to the incorrect addition of too much product.


Iron oxide is neither a hazardous material nor a water contaminant, and it can be handled using simple equipment and without expensive metering systems. A plant sustains no corrosion damage. The product requires no special storage and personnel need not be trained in accordance with dangerous goods handling regulations (e.g. the German Ordinance on Dangerous Goods)


Bayoxide® E 16 removes hydrogen sulfide in the fermentation reactor so effectively that the resulting biogas, in most cases, can be used directly. When it comes to injection into the public grid, the residual hydrogen sulfide content is already so low that the cost of secondary biogas desulfurization, e.g. by activated carbon gas treatment, is significantly reduced.

The Global Competence Center Specialties will gladly answer individual customer inquiries with respect to this field of application or provide further information about LANXESS pigments.