Experimental and Kinetic Analysis of H2S Removal in a Polyurethane Foam/Palm Fiber-Based Biofilter with No pH Control

Exposure to hydrogen sulfide, a toxic and malodorous pollutant, is a public health concern. Therefore, its removal from polluted air streams is crucial. This study aimed to evaluate the removal of H2S in a biofilter packed with a mixture of polyurethane foam and palm fiber with no pH control. The kinetics of H2S biofiltration were also analyzed using Michaelis–Menten and Haldane models. The biofilter was operated for 72 days at empty bed retention times (EBRT) of 47 and 30 s. During the operation of the biofilter, in addition to measurement of inlet and outlet H2S concentrations, the concentration profiles along the reactor length were also monitored. Moreover, the sulfate contents and pH values of packing bed and leachate were measured. During H2S biofiltration, the sulfate contents of packing bed and leachate increased and the leachate was acidified. Under this condition, the biofilter provided removal efficiency (RE) > 99% for inlet H2S concentrations up to 380.0 mg m−3 at EBRT of 47 s. Moreover, a maximum elimination capacity (ECmax) of 36.0 g m−3h−1 with RE of 98.0% was obtained at EBRT of 47 s. The experimental EC values were better fitted to Haldane kinetic, indicating the inhibitory effect of high H2S loads on its removal in the biofilter without controlling pH and under acidic conditions. Overall, efficient removal of H2S was obtained in a polyurethane foam/palm fiber-based biofilter with negligible pressure drop even without controlling pH.