Effect of Polyaniline and Graphene Oxide Modified Carbon Felt on Adsorption and Immobilization of Acidithiobacillus ferrooxidans

Biological desulfurization plays an increasingly important role in desulfurization industry. A strain of Acidithiobacillus ferrooxidans ZJ-2 with high Fe2+ oxidizing efficiency was in this study isolated and screened to remove hydrogen sulfide from biogas. To further improve its oxidation efficiency, A. ferrooxidans ZJ-2 was immobilized using carbon felt (CF), modified with graphene oxide (GO) and polyaniline (PANI), as immobilized carrier. The effects of immobilization on strain's Fe2+ oxidation efficiency and impact of PANI and GO on CF were also investigated. Raman spectra and atomic force microscopy showed that CF was successfully modified using GO and PANI. Cyclic voltammetry and electrochemical impedance spectroscopy measurements revealedIP: that182.75.the 48.10 electrochemicalOn: Tue, 22proper Febties of2022 modified12:43:28CF were improved, presenting the following trend in conductivity: CF< GO-modified CF (GO-CF) < PANI-modified CF (PANI-CF) PANI/GO-modified CF (PANI/GO-CF). The resistance of modified CF was lower than that of umodified CF, and exhibited the following trend: CF GO-CF > PANI-CF > GO/PANI-CF. While PANI-CF inhibited growth of free and immobilized A. ferrooxidans ZJ-2, GOCF was conducive to microbial growth and increased cell density and oxidation ability of A. ferrooxidans ZJ-2. Thus, the present study developed an immobilized bacterial carrier that had better conductivity and lower resistance and was efficient in immobilizing A. ferrooxidans and could be used for biogas desulfurization in biological and biochemical combined reactors.

Automated summary

Biological desulfurization using Acidithiobacillus ferrooxidans ZJ-2 strain immobilized on carbon felt modified with graphene oxide and polyaniline was investigated. The results showed that graphene oxide modification promoted microbial growth and oxidation ability, while polyaniline modification inhibited microbial growth. This study provides a novel immobilized carrier for biogas desulfurization.