Three different biochars as cost-effective substitutes for activated carbon (AC) were tested for their
hydrogen sulfide (H2S) adsorption ability. The biochars were produced from camphor (SC), bamboo
(SB), and rice hull (SR) at 400 C by oxygen-limited pyrolysis. The surface area (SA), pH, and Fourier trans-
form infrared spectras of the biochars and AC were compared. The maximum removal rates and the sat-
uration constants were obtained using the Michaelis–Menten-type equation. The three biochars were
found to be alkaline, and the SAs of the biochars were much smaller than that of the AC. The H2S break-
through capacity was related to the local pH within the pore system of the biochar. The order observed in
terms of both biochar and AC adsorption capacity was SR > SB > SC > AC. SR efficiently removed H2S
within the inlet concentration range of 10–50 lL/L. Biochars derived from agricultural/forestry wastes
are a promising H2S adsorbent with distinctive properties.