Treatment of chloramphenicol-contaminated soil by microwave radiation

This paper describes the microwave (MW) treatment of soil contaminated by chloramphenicol (CAP), using granular activated carbon (GAC) as MW absorbent. It was found that the addition of GAC effectively increased the temperature of soil. Large MW power and GAC dosage were beneficial for a completed decomposition of CAP. The effect of initial CAP concentration on decomposition was minute and a small scale of soil/GAC was disadvantageous. The degradation mechanism by MW radiation was also explored. The decomposition product of 4-nitrobenzoic acid after MW radiation was confirmed by LC-MS. The analysis by GC-MS and FTIR proved that parts of the decomposed fragment of CAP reacted with soil organic matters and formed compounds with larger molecular weight than CAP, but the concentration of each product was extremely low. It was suggested that MW radiation was an alternative technology for the treatment of antibiotics-contaminated soils. (C) 2009 Elsevier Ltd. All rights reserved.