title: Effect of interlayer cations of montmorillonite on the biodegradation and adsorption of crude oil polycyclic aromatic compounds.
abstract: Cation exchange capacity, surface acidity and specific surface area are surface properties of clay minerals that make them act as catalysts or supports in most biogeochemical processes hence making them play important roles in environmental control. However, the role of homoionic clay minerals during the biodegradation of polycyclic aromatic compounds is not well reported. In this study, the effect of interlayer cations of montmorillonites in the removal of some crude oil polycyclic aromatic compounds during biodegradation was investigated in aqueous clay/oil microcosm experiments with a hydrocarbon degrading microorganism community. The homoionic montmorillonites were prepared via cation exchange reactions by treating the unmodified montmorillonite with the relevant metallic chloride. The study indicated that potassium-montmorillonite and zinc-montmorillonite did not enhance the biodegradation of the polycyclic aromatic hydrocarbons whereas calcium-montmorillonite, and ferric-montmorillonite enhanced their biodegradation significantly. Adsorption of polycyclic aromatic hydrocarbons was significant during biodegradation with potassium- and zinc-montmorillonite where there was about 45% removal of the polycyclic aromatic compounds by adsorption in the experimental microcosm containing 5:1 ratio (w/w) of clay to oil.
authors.affiliation: School of Civil Engineering and Geosciences, University of Newcastle Upon Tyne, NE1 7RU, United Kingdom. Electronic address: ugouzochukwu@yahoo.com.
authors.forename: Uzochukwu C
authors.initials: UC
authors.lastname: Ugochukwu
authors.affiliation: School of Civil Engineering and Geosciences, University of Newcastle Upon Tyne, NE1 7RU, United Kingdom.
authors.forename: David A C
authors.initials: DA
authors.lastname: Manning
authors.affiliation: School of Civil Engineering and Geosciences, University of Newcastle Upon Tyne, NE1 7RU, United Kingdom.
authors.forename: Claire I
authors.initials: CI
authors.lastname: Fialips
mesh_terms: D000327:Adsorption; D001546:Bentonite / Q000737:chemistry*; D001673:Biodegradation, Environmental; D002412:Cations / Q000737:chemistry; D008670:Metals / Q000737:chemistry*; D010578:Petroleum; D011084:Polycyclic Aromatic Hydrocarbons / Q000737:chemistry / Q000378:metabolism*; D012988:Soil Microbiology; D012989:Soil Pollutants / Q000737:chemistry / Q000378:metabolism*
chemical_list: D002412:Cations; D008670:Metals; D010578:Petroleum; D011084:Polycyclic Aromatic Hydrocarbons; D012989:Soil Pollutants; D001546:Bentonite
keywords: Adsorption; Biodegradation; Homoionic montmorillonites; Polycyclic aromatic compounds; Unmodified montmorillonite