The Effect of Co-Metabolism on Removal of Hexadecane by Microbial Consortium from Soil in a Slurry Sequencing Batch Reactor

Background: among alkanes, n-alkanes with medium chainhave been identified as the most important contaminants of thesoil. n-hexadecane (c16h34) with low solubility in water alsobelongs to this group and has been used by many researchers asa model contaminant. the present study aimed to investigate theeffect of the external source of carbon (glucose) as co-substrateon removal of hexadecane from the soil.methods: in this study, a slurry sequencing batch reactor (ssbr)was used as a pilot by a bacterial consortium, including bacteriumacinetobacter radioresistens, bacillus subtilis, and pseudomonasaeruginosa, in order to remove different concentrations ofhexadecane (1,4,7, and 10 percent).sampling was performed fourtimes during the sedimentation step. then, the samples wereanalyzed by gc-fid and the results were analyzed statistically.results: the results showed that hexadecane removal (%) by themicrobial consortium was higher in lower initial concentrationsin such a way that the biological removal of hexadecane wasrespectively 45.95%, 38.55%, 34.39%, and 32.40% in theconcentrations of 1%, 4%, 7%, and 10% on the third day.moreover, adding the external carbon source (glucose) on thefirst day caused a 16% increase in hexadecane removal, whichis 1.4 times more than the amount of hexadecane removal in theconditions without co-metabolism.conclusion: the results showed that ssbr could be used as anexit-situation effective method for hexadecane removal in lowconcentrations through considering the effective factors in itsfunction, such as dissolved oxygen, ph, and temperature. also,adding the secondary carbon source could be effective in hexadecaneremoval from the soil. yet, this effect might vary on different days.