A single catalyst of aqueous CoIII for deodorization of mixture odor gases: a development and reaction pathway study...

A constant generation of aqueous Co(III) active catalyst and its utility on various odor gases deodorization at electro-scrubbing process is the primary investigation. The Co(III) activation and regeneration for continuous use is established by electrochemical undivided cell in H₂SO₄ medium. The generated aqueous Co(III) is then applied to simultaneous deodorization of simulated odor gases, namely, ammonia, trimethylamine, hydrogen sulfide, methyl mercaptan, and acetaldehyde, for municipal waste treatment plant emissions. The electro-scrubbing process results indicated that deodorization is almost complete at a low gas flow rate of 30 L min(-1). FTIR and pH studies demonstrated that amine compounds are removed via complex formation with H₂SO₄ and Co(III). In the case of sulfur compounds, deodorization of methyl mercaptan and hydrogen sulfide are removed by the Co(III)-MEO (Co(III)-mediated electrocatalytic oxidation) process via the formation of acetic acid as intermediate and SO₄(2-) as a product. Also, acetaldehyde deodorization results obtained by pH, total acidity and CO₂ analyses evidence the process follow Co(III)-MEO. The constant generation of aqueous active Co(III) and an electro-scrubbing process offers promise as a means of removing odorous waste gases from gaseous emissions.