Nazari, Elmira

This thesis explores the remediation of naphthenic acids (NAs) from oil sands process-affected water (OSPW) using activated carbon (AC) derived from petroleum coke (PC) chemically activated with potassium hydroxide. The research aims to identify the most effective method for the adsorptive removal of NAs by optimizing the use of economically viable KOH quantities and to apply Fourier Transform Ion Cyclotron Resonance Mass Spectrometry (FT-ICR-MS) for species-specific detection and characterization of NAs, crucial for targeting specific NAs in future studies.Prior research focused on single-species adsorption, establishing a foundational understanding of non-competitive adsorption before applying these findings to more complex NA mixtures and OSPW. This study builds upon this foundation, addressing a significant gap in the literature concerning the use of petcoke-derived AC with low KOH ratios and short activation times, which are economically advantageous for large scale applications. In this thesis, a comprehensive investigation into the kinetics and isotherms of NA adsorption on various ACs including PAC (petroleum coke AC), PWAC (pore-widened AC), HAC (heat-treated wood-based AC), and CAC (commercial AC) was conducted. The study specifically examines the adsorption behaviors of seven model NAs, reflecting the diverse molecular structures present in real world OSPW. The research also explores the impact of pore widening techniques on the adsorption efficiency of ACs, hypothesizing that increased mesoporosity enhances the adsorption of NA compounds. The findings demonstrate that FT-ICR-MS is an essential tool for precisely characterizing the NA species in OSPW, revealing that pore-widened ACs significantly improve the adsorption of NAFCs. This thesis contributes to the field of environmental remediation by offering new insights into the optimization of AC for NA removal, emphasizing the importance of surface chemistry and mesoporosity in enhancing adsorption efficiency. The study's outcomes have significant implications for the treatment of OSPW, providing a scalable and cost-effective solution to mitigate the environmental impacts of oil sands production.

Author Keywords: activated carbon, FT-ICR-MS, naphthenic acids, oil sands, petroleum coke, process-affected water