Mechanism and process optimization for H2S removal by plant-derived deodorant

Plant-derived deodorant shows exciting prospect for odorous gas control, while controversy still exists on its effect of removing the malodorous substances with the fact that the removal mechanism and parameter opti-mization of this deodorization technology were rarely reported. Herein, a laboratory-scale bubbling absorption tower was used to conduct orthogonal test designed with three factors of five levels to investigate the efficiency of plant-derived deodorant to remove hydrogen sulfide (H2S). Compared with water, the aqueous solution of plant-derived deodorants could effectively remove H2S with a maximum removal efficiency of 99.99%. In particular, the removal efficiency of deodorant was about 40% higher than that of water at the H2S concentration of 70 mg/m3. After treated by the aqueous solution of plant-derived deodorants, the outlet concentration of H2S could be lower than 0.02 mg/m3, meeting the requirement of the odor pollutant emission standards in many countries, which exhibited the feasibility of using it an effective way to control H2S. Among the parameters including air input, concentration of H2S, and concentration of plant-derived deodorant, concentration of deodorant was the parameter that presented the most significant impact on the deodorization effect. The calculation results of absorption and reaction parameters showed that the removal of H2S by plant-derived de-odorants is a process controlled by chemical absorption.