Simulated Ageing of Crude Oil and Advanced Oxidation Processes for Water Remediation since Crude Oil Pollution

Abstract

Crude oil can undergo biotic and abiotic transformation processes in the environment. This article deals with the fate of an Italian crude oil under simulated solar irradiation to understand (i) the modification induced on its composition by artificial ageing and (ii) the transformations arising from different advanced oxidation processes (AOPs) applied as oil-polluted water remediation methods. The AOPs adopted were photocatalysis, sonolysis and, simultaneously, photocatalysis and sonolysis (sonophotocatalysis). Crude oil and its water-soluble fractions underwent analysis using GC-MS, liquid-state 1H-NMR, Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS), and fluorescence. The crude oil after light irradiation showed (i) significant modifications induced by the artificial ageing on its composition and (ii) the formation of potentially toxic substances. The treatment produced oil oxidation with a particular effect of double bonds oxygenation. Non-polar compounds present in the water-soluble oil fraction showed a strong presence of branched alkanes and a good amount of linear and aromatic alkanes. All remediation methods utilised generated an increase of C5 class and a decrease of C6–C9 types of compounds. The analysis of polar molecules elucidated that oxygenated compounds underwent a slight reduction after photocatalysis and a sharp decline after sonophotocatalytic degradation. Significant modifications did not occur by sonolysis.

Zinc Oxide NPs as Solar Photo-Catalysis for Water Disinfection

“…On the other hand, among semiconductors, titanium dioxide (TiO2) has been the strongest material studied in recent years, utilizing semiconductor oxides as a photocatalyst (He et al, 2020). Being obligated to repay to its own low production expense and excellent chemical security, it has been extensively worked with in photo-degradation of all-natural materials, like those with a higher running of nitrogen-containing natural substances (Khan, Rahaman, Al-Jubayer, & Islam, 2015), unstable organic substances (Magalhaes, Andrade, Nunes, & Mendes, 2017) as well as chemicals (Lelario, Bianco, Bufo, & Scrano, 2021) along with a UV source of light (Alaton & Balcioglu, 2001), the request of TiO2 making use of solar energy is extremely limited by its own big band void (3.2 eV) and reduced quantum effectiveness. Substantial attempts like doping (Monneyron, Manero, Foussard, Benoit-Marquié, & Maurette, 2003), development of nanocomposites (Autin et al, 2013), surface area alteration, color sensitization (A.-n. and rare-earth element (Mianxince, Liang, Tianliang, & Xiaoyong, 2008) have been created towards prolonging photo response and also photoactivity of TiO2 in noticeable lightweight area.…”