Improved methanogenesis in anaerobic wastewater treatment by magnetite@polyaniline (Fe3O4@PANI) composites

The magnetite@polyaniline (Fe3O4@PANI) composites with different Fe3O4 loadings were prepared, and their effect on methane production in anaerobic systems was investigated. The Fe3O4@PANI composite with a 40% loading of Fe3O4 showed a better performance on accelerating methane production rate than other composites. The methane production rate was increased by 26.98% at the Fe3O4@PANI dosage of 0.6 g L-1. The results of the contact angle and CLSM revealed that Fe3O4@PANI had a good bio-affinity and contact directly with bacteria and archaea. Then the mechanisms related to the enhancement of methane production by the composites were explored by the species annotation and enzyme activity. It showed that Fe3O4@PANI promoted the enrichment of DIET-related functional bacteria and archaea and improved the enzyme activity related to the acetoclastic methanogenic pathway.

Automated summary

Fe3O4@PANI composites can accelerate methane production rate, have good bio-affinity, and improve enzyme activity related to the acetoclastic methanogenic pathway.