Petroleum Industry Wastewater Treatment for Phenolic Compound Removal Using Modified Date Seed-Based Biochar

Abstract Industries play important roles in modern economies by providing essential energy products, supporting industrial growth, and driving technological innovation. However, these Industries are among the biggest culprits in dumping billions of pounds of toxic pollution into waterways every year. These compounds harm human health and wildlife. Therefore, it is very imperative to develop and implement effective wastewater treatment. Based on that, this study has been carried out to apply modified date seed-based biochar as an adsorbent material to remove phenolic compounds, such as p-nitrophenol, from the aqueous solution leaving the petroleum industry. The research work developed and utilised modified date-seed biochar for the extraction of p-nitrophenol from petroleum industry wastewater by exploring the impact of various operational factors, which were the biochar dosage, the contact duration, the initial concentration of phenolic compounds, the temperature and the pH level on the efficiency of removing p-nitrophenol using the chemically modified date-seed biochar adsorbents. The study successfully carried out the chemical modification of date-seed biochar with MgCl2•6H2O and characterised the modified adsorbent using Fourier transform infrared spectroscopy (FTIR) and X-Ray diffraction (XRD). The results confirmed successful preparation and surface modification of the biochar. Preliminary adsorption tests demonstrated the effectiveness of the modified date-seed biochar in removing p-nitrophenol from aqueous solutions, achieving a maximum removal efficiency of 94.94% under optimal conditions (temperature of 25 °C, pH of 6, duration of 60 minutes and dosage of 0.2 mg). The adsorption performance significantly improved with surface modification. Subsequent studies on adsorption indicated that the equilibrium data could fit well with Freundlich and Langmuir models, with a Langmuir adsorption value of a maximum value of 43.19 mg/g and an R2 of 0.8207, indicating monolayer adsorption on a homogenous surface. The kinetic studies carried out further showed that the pseudo-second-order model best described the adsorption rate, suggesting chemisorption. Also, the modified date-seed biochar was found to exhibit great potential as an efficient, low-cost, reusable and sustainable adsorbent for removing p-nitrophenol and other contaminants from aqueous solutions. Therefore, it is recommended that modified date seed-based biochar should be applied by the petroleum industries in removing phenolic compounds such as p-nitrophenol from the industry wastewater.