Performance optimization of the fungal biodegradation of α-pinene in gas-phase biofilter

A Ophiostoma species using α-pinene as the sole source of carbon and energy converted it into biomass, carbon dioxide and water. The strain was inoculated in a biofilter fed α-pinene polluted air, and it remained the dominant biocatalyst throughout the study. Near complete removal was observed up to a load of 100 g m−3 h−1, while 89% removal efficiency was reached at an elimination capacity of 143 g m−3 h−1. The influence of gas flow rate, pollutant concentration and load was evaluated. For a similar load, the highest removal efficiency and corresponding elimination capacity were reached at the lowest flow rate and at an inlet concentration of 2.47 g m−3. Oxygen had a significant effect on the removal efficiency since the maximum α-pinene degradation rate exceeded 187 g m−3 h−1 at 45% oxygen in the inlet air suggesting that at high loads oxygen transfer becomes limiting. Biokinetic studies led to a good fit between experimental data and mathematical equations, yielding a calculated maximum α-pinene degradation rate of 198.42 g m−3 h−1 with a half-velocity constant, KS, of 0.76 g m−3.