Biodegradation of high-molecular-mass heteroatomic components of heavy oil

Microbial degradation of resins and asphaltenes by indigenous soil microflora has been studied under laboratory conditions on model soil systems. It has been shown that high-molecular-mass heteroatomic components of oil are available for the oxidation by soil microorganisms; within 180 days of the experiment the utilization of resins and asphaltenes was 41.5 and 35.0 wt %, respectively. Analysis of the residual products of biodegradation showed a marked change in the composition of high-molecular-mass heteroatomic components. Biodegradation of resins and asphaltenes occurs predominantly with the “detachment” of peripheral paraffin structures, the aromatic ring is converted substantially less.