Polymer degradation anaerobic

Arnosti, C., and D. J. Repeta. 1994b. Oligosaccharide degradation by anaerobic marine bacteria Characterization of an experimental system to study polymer degradation in sediments. Limnology and Oceanography 39 1865-1877. 

Compounds with a high oxidation state such as those with a lot of chlorine are recalcitrant to further oxidation. These compounds must therefore be degraded anaerobically. Chlorine is substituted by hydrogen or HC1 is removed and a double bond is introduced, for example, DDT that may be dechlorinated to 4,4 -dichlorodiphenyl-dichloroethane (DDD) by anaerobic processes or slowly converted to 4,4 -dichlorodiphenyldichloroethylene (DDE) (Stenersen, 1965). Compounds such as mirex and hexachlorobenzene are extremely recalcitrant to degradation, and microorganisms do not attack the highly fluorinated or chlorinated polymers, such as Teflon and PVC. 

Day, M., Shaw, K., and Cooney, J.D., 1994, Biodegradability an assessment of commercial polymers according to the Canadian method for anaerobic conditions. J. Environ. Polym. Degrad. 2 121-127. 

P.K. Shin, M.H. Kim, and J.M. Kim, Biodegradabihty of degradable plastics exposed to anaerobic digested sludge and simulated landfill conditions. J. Environ. Polym. Degrad. 5(1), 33-39 (1997). 

Dominant groups of microorganisms and the degradative pathways associated with polymer degradation are often determined by the environmental conditions. When O2 is available, aerobic microorganisms are mostly responsible for destruction of complex materials, with microbial biomass, CO2, and H2O as the final products. In contrast, under anoxic conditions, anaerobic consortia of microorganisms are responsible for polymer deterioration. The primary products will be microbial biomass, CO2, CH4 and H2O under methanogenic (anaerobic) conditions (Barlaz et al., 1989) (e.g., landfills/compost) (Fig. 8.5). 

Gartiser S, WaUrabenstein M, Stiene G. Assessment of several test methods for the determination of the anaerobic biodegradabihty of polymers. J Environ Polym Degrad 1998 6 159-173. 

Budwill, K., Fedorak, P.M. and Page, W.J. (1996), Anaerobic microbial degradation of poly(3-hydroxyalkanoates) with various terminal electron acceptors , J. Environ. Polym. Degrad. 4 (2), 91—102. 

Kolstad, J. J., Vink, E. T. H., De Wilde, B., Debeer, L. (2012). Assessment of anaerobic degradation of Ingeo polylactides under accelerated landfill conditions. Polymer Degradation and Stability, 97, 1131—1141. 

Massardier-Nageotte, V., Pestre, C., Cmard-Pradet, T., Bayard, R., 2006. Aerobic and anaerobic biodegradabdity of polymer films and physico-chemical characterization. Polym. Degrad. Stabd. 91, 620—627. 

Regeneration of the reduced metal ion by redox reaction during catalysis is essential to continue PO degradation. Fe is the thermodynamically favored oxidation state for iron under aerobic and alkaline conditions, whereas Fe is favored under anaerobic and acidic conditions. Under most disposal and environmental conditions Mn " is favored. It is therefore unlikely that a particular metal catalyst will perform equally well in a wide range of disposal situations. Due to environmental pH values it is difficult for such catalysts to be recycled for further free radical generation. Both Fe and Fe " salts can precipitate as insoluble oxides or sulfides under environmental conditions, reducing the polymer degradation potential. 

A schematic of polymer degradation under aerobic and anaerobic conditions... 

Gu J-D, Gu J-G, Shi HC, li XY (2001b) Simulating anaerobic landfill conditions in bioreactors and testing polymer degradability using poly(P-hydroxybutyrate-co-16 % valerate) and cellulose acetetes (DS 1.7 and 2.5) Water Sci Technol... 

Compared to investigations of polymer degradation under aerobic conditions, very little information is available in the literature for degradation of plastics under anaerobic conditions. Again most of the investigations published are focused on PHA. 

Highly toxic to humans and not effective against anaerobes. Caused increase rate of polymer degradation. Deactivated by presence of H S. ... 

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