Naphthalene

typical of polycyclic aromatic hydrocarbons

is highly poisonous and hardly degradable. As the typical petroleum hydrocarbon composition

it is a severe environmental pollutant

and therefore there exists great difficulty in the bioremediation of oil-contaminated sites. Due to its poor water solubility

researches on naphthalene degradation are hindered seriously. In this paper

the strain of Acinetobacter johnsonii isolated from waste oil is employed to study naphthalene biodegradation with the ability both to degrade petroleum hydrocarbon and to wet inorganic impurities. The reaction conditions are optimized based on the researches on degradation factors and the biodegradation characteristics of naphthalene are manifested in the range of 50 to 2000 mg·L-1. The dynamics behavior of A. johnsonii is studied on the degradation of naphthalene through the comparison of the Monod model and the Haldane model. The results indicated that the strain could utilize naphthalene as sole carbon and energy source to metabolize and 2000 mg·L-1 naphthalene could be entirely degraded within about 146 h at 5% inoculum volume and 37℃. The Haldane model is suitable to describe cell growth and the substrate degradation behaviors while the Monod model is appropriate to depict naphthalene biodegradation with low initial concentration.