Groundwater pollution from oil spills is a serious environmental problem. Petroleum hydrocarbons like benzene, toluene, xylene, and PAHs can spread into water and create risks for human health, animals, and ecosystems. In this study, Abhijeet Pathy, the first author, shows how crop straw biochar can help solve this issue. Instead of using expensive treatment systems, biochar made from canola straw offers a simple, natural, and sustainable solution for cleaning contaminated groundwater.
Material Method
The researchers collected groundwater from Alberta, Canada, and tested it using crude oil contamination. They focused on 12 petroleum hydrocarbons, including BTEX compounds, F1 and F2 hydrocarbons, and PAHs.
Material Method
The researchers collected groundwater from Alberta, Canada, and tested it using crude oil contamination. They focused on 12 petroleum hydrocarbons, including BTEX compounds, F1 and F2 hydrocarbons, and PAHs.They produced biochar from canola straw using pyrolysis at 450–500°C in an oxygen-limited environment. Different biochar dosages of 0.5, 1, and 2 g/L were tested to measure how effectively the biochar removed pollutants. They also used FTIR, XPS, and BET analysis to study surface area, pores, and functional groups responsible for adsorption.
Results
The results were very strong. Hydrocarbon concentrations dropped by more than 40% within the first minute after adding biochar. BTEX compounds showed over 95% removal within 7 days, while some petroleum hydrocarbons reached over 99% removal at 2 g/L biochar dosage.
F2 hydrocarbons were almost completely removed within 24 hours. PAHs also showed nearly 100% removal. The study found that adsorption happened mainly through chemisorption, diffusion, hydrophobic interactions, and π-π bonding between pollutants and biochar surface groups.
Conclusion
This study proves that crop straw biochar is a powerful and low-cost material for groundwater cleanup. Waste agricultural materials like canola straw can become valuable tools for environmental protection instead of being discarded.
Abhijeet Pathy and his team showed that biochar not only removes harmful petroleum hydrocarbons effectively but also supports carbon sequestration and a circular economy. This makes biochar an excellent solution for cleaner water and a more sustainable future.
Reference
Pathy, A., Naeth, M. A., & Chang, S. X. (2025). Crop straw biochar enhances hydrocarbon adsorption in ground water. Chemosphere, 393, 144775.
