Browsing by Author "Enemugwem, Rachel Itongnte"

Now showing 1 - 1 of 1
  • Thumbnail Image
    ItemOpen Access
    Remediation of crude oil polluted soil with cow dung and Pennisetum purpureum zinc oxide nanoparticles
    (Federal University of Technology, Owerri, 2025-02) Enemugwem, Rachel Itongnte
    This study investigated the remediation of crude oil polluted soil with cow dung and Pennisetum purpureum zinc oxide (ZnO) nanoparticles. Zinc oxide nanoparticles were synthesized using an aqueous leaf extract of Pennisetum purpureum and cow dung. The ZnO nanoparticles were characterized by ultraviolet–visible spectroscopy (UV–Vis), Fourier transform infrared spectroscopy (FTIR), X-Ray diffraction (XRD) and transmission electron microscopy (TEM). The phytochemical properties of Pennisetum purpureum, cow dung and ZnO nanoparticles were assessed using gas chromatography mass spectrometry (GC-MS). One kilogram soil was polluted invitro with 100 mL Bonny light crude oil. This study was carried out for 42 days. The concentrations of polycyclic aromatic hydrocarbons (PAHs), heavy metals, Benzene, Toluene, Ethylbenzene and Xylene (BTEX), total organic carbon (TOC), total petroleum hydrocarbon (TPH), nitrogen, phosphorous, pH, total heterotrophic bacteria (THB) and total hydrocarbon utilizing bacteria (THUB) count were determined in unpolluted, polluted and remediated soil using standard analytical methods. The major bioactive compounds in Pennisetum purpureum were linoleic acid (18.89%), cis-13-octadecenoic acid (15.74%), 1,2-benzisothiazole (6.69%), 11-octadecenoic acid (5.53%), oleic acid (5.01%), the major bioactive compounds in cow dung were trans-13-octadecenoic acid (12.03%), 8, 11 – octadecadienoic acid (8.29%), 9octadecanoic acid (8.11%), cycloeisane (7.43%). UV–vis spectra showed absorption peaks at 367nm (3.38 eV) for cow dung ZnO nanoparticles and 370nm (3.35 eV) for Pennisetum purpureum ZnO nanoparticles. FTIR analyses identified functional groups (C-O, O-H, CH, C≡C, C=C, N-O) and chemical bond formations in Pennisetum purpureum and cow dung ZnO nanoparticles. XRD results revealed ZnO nanoparticle’s crystalline structure, phase composition and average particle size of 23.37nm (Pennisetum purpureum ZnO nanoparticles) and 18.17nm (cow dung ZnO nanoparticles). The TEM images showed that the biosynthesised ZnO nanoparticles were spherical in shape with an average mean particle size of 3.47nm for cow dung ZnO and 15.21nm for Pennisetum purpureum ZnO nanoparticles at 100nm magnification. The remediation of crude oil polluted soil with cow dung and Pennisetum purpureum ZnO nanoparticles was dose dependent (20g and 40g). The pH of the polluted soil was acidic and alkaline in treated soil. There was a significant reduction (p<0.05) in the concentrations of heavy metal (As, Cr, Hg, Zn, Ni), nitrogen, zinc, phosphorous, PAH, BTEX, TOC, TPH on the crude oil polluted soil treated with cow dung and Pennisetum purpureum ZnO nanoparticles because of the photocatalytic activity of the ZnO nanoparticles on the pollutants. Total heterotrophic bacterial and total hydrocarbon utilizing bacteria count increased progressively during the 42 days study period. The higher concentrations (40g) of the nanoparticles were more efficient for soil remediation than lower concentrations (20g). The results from this study showed that cow dung and Pennisetum purpureum ZnO nanoparticles are photocatalysts and has the potential to degrade pollutants and reduce the clean - up time.