Performance of Sweet Potato’s Leaf-Derived Activated Carbon for Hydrogen Sulphide Removal from Biogas

Abstract

In this study, sweet potato leaf activated carbon (SpLAC) was prepared by the chemical activation method using KOH and applied as an adsorbent for H2S removal from biogas. The study focused on the understanding of the effect of carbonization temperature (Tc), varying KOH : C activation ratio, flow rate (FR) of biogas, and mass of SpLAC on sample adsorption capacity. The BET analysis was performed for both fresh and spent activated carbons as well as for carbonized samples, which were not activated; also, the activated carbon was characterized by XRF and CHNS techniques. The results showed that removal efficiency (RE) of the SpLAC increased with increase carbonization temperature from 600 to 800°C and the mass of sorbent from 0.4 g to 1.0 g. The optimal test conditions were determined: 1.0 g of sorbent with a KOH : C ratio of 1 : 1, Tc=800°C, and FR=0.02 m3/h which resulted in a sorption capacity of about 3.7 g S/100 g of the SpLAC. Our findings corroborated that H2S removal was contributed not only by the adsorption process with the pore available but also by the presence of iron in the sample that reacted with H2S. Therefore, upon successful H2S sorption, SpLAC is suggested as a viable adsorbent for H2S removal from biogas.

A New Novel Derived from Sodium Carbonate for The Elimination of Hydrogen Sulfide from Biogas

“…The uptake ability (SC) and the removal efficiency (RE) were obtained by the use of equations 1 and 2 [18] *100%…”

“…For a sorbent, to be durable before regeneration and reuse there is a need for having a long and large bed reactor that can allow for more mass of sorbent. Literature shows that sweet potato leaves with 1kg mass showed a sorption capacity was 0.37 g/100 g whereas removal efficiency was 95% [18], while Mrosso et al [30] use the mass of 0.6g for the elimination of H 2 S from biogas that showed a sorption ability was 0.37 g/100 g and removal efficiency RE 95%. Based on the current study, it was noted that H 2 S molecules had more chances to interact with 75 g of soda ash in comparison with 50, and 25 g. Thus the highest RE and Sc were noted when using a mass of 75g.…”