Potential for Biochar-Based Removal and/or Inactivation of Waterborne Viruses.

Biochar is a black carbon co-product resulting from the pyrolysis of bioenergy feedstocks. A study was conducted to investigate the use of biochar (derived from corn stover) for the removal/inactivation of waterborne viral contaminants. Bacteriophage MS2 was combined in 200 ml PBS (phosphate buffered saline, pH 7.4 ± 0.2) with 50 mg of finely-ground biochar. The solution was mixed at 380 rpm for two hours and passed through a 0.2 µm filter for phase separation. The resulting filtrate was assayed for PFU (Plaque Forming Units) quantification according to Standard Methods for the Examination of Water and Wastewater. Additionally, powdered activated carbon (PAC), a known viral sorbent, was used as a positive control for viral inactivation. A solution containing only MS2 and PBS was used as the baseline for quantification and relative sterility of the biochar was determined by assaying solutions containing only biochar and PBS. The PAC removed 99.8% of MS2 from solution. In contrast, the biochar had no discernable impact on MS2 numbers in solution. These results suggest that further processing of biochar may be necessary in order for it to be effectively used for the removal of viral contaminants from aqueous matrices.