Hydrogen Sulfide Removal by Iron Oxide-Based Clay from Biogas for Community Use

Abstract

The purpose of this study was to absorb the hydrogen sulfide (H2S) produced by biogas system for local community six absorbents, namely activated carbon, shredded rusty iron and iron oxide-based clay with 4 different size distributions that were tested by employing Completely Randomized Design (CRD). The results showed that iron oxide-based clay from a groundwater supply with smallest size (8.73 mm in diameter) was the most effective absorbent in removing the H2S judging by security level of biogas users and security level of the engine of 368 and 406 minutes, respectively. However, the security level of the engine of the smallest iron oxide was not significantly different from that of medium size (12 mm in diameter) in 325 minutes. For the durability of absorbent determined from H2S was less than 500 ppm, the iron oxide with the smallest size was also effective with the best removal (506 minutes) but was not significantly different from those of the medium size (491 minutes) and the mixed size (435 minutes). Therefore, the smallest iron oxide-based clay was selected for the technology transfer to rubber tree farmers and fishermen in the south of Thailand.