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Excessive exposure to hydrogen sulfide (H 2 S) and acetic acid (CH 3 COOH) gases is extremely dangerous in a confined space. An effective indoor air pollutant removal porous carbon filter was developed using NaOH impregnated on activated carbon (NaOH/AC) for the adsorption of H 2 S and CH 3 COOH. Activated carbon (NaOH/AC) filter was characterized using various methods, indicating good physical and chemical properties (especially -OH functional groups) for the adsorption of air pollutants. The prepared NaOH/AC filter was cured at different curing temperatures and residence times to understand the effect of the curing conditions on the adsorption performance. The best results were obtained with NaOH/AC filter cured at 100 • C for 20 minutes as it eliminated the initial concentration of 400 ppm of CH 3 COOH in 15 minutes and H 2 S in 30 minutes at 20 • C and 60% relative humidity. Isotherm and kinetic models were used to analyze the adsorption process. Langmuir isotherm and pseudo-second order kinetic models provided the best fit to the adsorption of CH 3 COOH and H 2 S on NaOH/AC filter. The adsorption mechanism was controlled by the intraparticle diffusion combined with film diffusion. The maximum adsorption capacity of NaOH/AC filter was 473 mg/g for H 2 S adsorption, and 550 mg/g for CH 3 COOH adsorption. In addition, the spent NaOH/AC filter was regenerated for reuse.This study is expected to develop low-cost and effective porous carbon filter using NaOH-modified activated carbon for indoor air purification.

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In this study, a removal technique of porous activated carbon filter was developed using copper impregnated on commercially available cocoa activated carbon (Cu/AC) for the removal of toxic pollutant gases (trimethylamine [TMA] and hydrogen sulfide [H2S]). Cu/AC (filter) was characterized with Scanning electron microscope (SEM), Energy dispersive X‐ray spectroscopy (EDS), Thermogravimetric analysis (TGA)/Differential thermal analysis, proximate analysis, Carbon, hydrogen, nitrogen, sulfur (CHNS)/O, and Brunauer–Emmett–Teller, the results indicated the Cu/AC possesses good physical and chemical characteristics and is suitable for adsorption of air pollutants. The Cu/AC filter exhibited excellent adsorption capacity for the removal of TMA (qe = 654.8 mg/g) and H2S (qe = 220.37 mg/g). The isotherm and kinetic models were applied to analyze the adsorption properties and adsorption mechanism. Langmuir isotherm showed best fit for the adsorption of TMA and H2S, whereas the pseudo‐first‐ and second‐order kinetic models best fitted in describing the adsorption of H2S and TMA, respectively. Also, the adsorption process for the removal of TMA and H2S was controlled by the intraparticle diffusion model. The H2S‐adsorbed Cu/AC filter can be regenerated but not lasting too many cycles. Techno‐economic analysis and life‐cycle analysis (LCA) were performed at a plant scale. Production costs were ¢1.37 for cocoa AC filter and ¢10.13 for activated rice husk (ARH) filter. Also, the LCA result for during the filter production was estimated to be 2.52 kg CO2‐eq for cocoa AC filter and 4.47 kg CO2‐eq for ARH filter. This study proves the competitiveness compared to ARH filter of the previous study in the adsorption performance and the filter production cost.