Performance and microbial community evolution of toluene degradation using a fungi-based bio-trickling filter

Fungi have their unique advantages in capturing and degrading hydrophobic VOCs. To study the performance of fungi-based bio-trickling filters (BTFs) with respect to the degradation of toluene, and the succession process of the fungal colony under different operating conditions, a three-layer BTF packed by dominant Fusarium oxysporum immobilized with ceramic particles were set up. The fungal BTF started quickly within 7 days and restarted less than 7 days after starvation; its average RE was higher than 92.5% when the toluene inlet loading rate (ILR) ranging from 7.0 to 100.9 g m^-3 h^-1 at steady state. Moreover, the maximum elimination capacity (EC) of 98.1 g m^-3 h^-1 was obtained at a toluene ILR of 100.3 g m^-3 h^-1. The microorganism analysis of time and space revealed that the dominant fungi Fusarium were replaced by Paramicrosporidium saccamoebae after a certain evolutionary period. The intermediate layer had more microbes and a more complex community than the other two layers, and was more suitable for the survival of the varieties of microbes.