Pellet activated carbon plays a crucial role in biogas desulfurization, efficiently removing hydrogen sulfide (H₂S) and organic sulfides primarily through a dual process of physical adsorption and chemical catalysis. Specific applications are as follows:

I. Core Reaction Mechanism

H₂S Removal:

H₂S reacts with O₂ on the surface of activated carbon to catalytically generate elemental sulfur, which is adsorbed into the pores, achieving a desulfurization rate of over 99%.

Reaction formula: H₂S + ½O₂ → S + H₂O (Elemental sulfur is adsorbed).

Organic Sulfide Removal:

Organic sulfur compounds such as COS are converted to H₂S through hydrolysis and then removed.

Reaction formula: COS + H₂O → H₂S + CO₂ (Further H₂S removal). 

II. Key Advantages

High-Efficiency Purification:

Suitable for biogas with H₂S content <0.3%, achieving H₂S content <10×10⁻⁹ g/m³ after purification.

Faster desulfurization speed and shorter contact time compared to the iron oxide method.

Easy Operation:

Low bed resistance, strong adaptability, and no need for frequent desulfurizing agent replacement.

Simultaneously removes H₂S and organic sulfur, achieving high purification levels.

III. Applicable Scenarios

Activated Carbon for Biogas Purification:

Used for fine removal of H₂S and organic sulfur in large and medium-sized biogas projects.

For example: desulfurization of biogas produced from agricultural waste fermentation.

Natural Gas Processing:

Used for sulfide removal from liquefied petroleum gas (LPG), natural gas, and other gas sources.

For example: natural gas desulfurization units in oil refineries.

IV. Technical Parameters

Desulfurization Rate: >99%.

H₂S content after purification: <10×10⁻⁹ g/m³.

Operating conditions: ambient temperature and pressure; no complex equipment required.