Green Solvent Strategies for BTX Remediation: From Pollution to Prevention in Industrial Wastewater

Aromatic hydrocarbons such as benzene, toluene, and xylene (BTX) are persistent pollutants in refinery wastewater and are known for their high toxicity, carcinogenicity, and adverse effects on human health and aquatic ecosystems. Prolonged exposure to BTX, even at low concentrations, has been linked to respiratory disorders, neurological impairment, and increased cancer risk, especially in communities located near petroleum refining facilities. This study investigates the application of a deep eutectic solvent (DES), a class of green solvents composed of hydrogen bond donors and acceptors, for the efficient extraction of BTX from refinery waste. Unlike conventional organic solvents, DESs are biodegradable, non-volatile, and tunable, making them safer for both the environment and human health. Using a TBAB–decanoic acid-based DES system, various compositions were synthesized, and only the one that remained stable was evaluated for BTX extraction efficiency through liquid–liquid extraction experiments. Key performance indicators included solvent mass fraction, stirring speed, time and temperature, and the reusability of the DES systems. Results revealed that DES exhibited high affinity for BTX compounds, with extraction efficiencies exceeding 80% for benzene and toluene under optimized conditions. The findings demonstrate the potential of DES not only as effective extractants but also as health-conscious alternatives in industrial wastewater treatment. This work highlights the relevance of green chemistry innovations in mitigating environmental and public health risks, aligning with global efforts toward cleaner water and safer communities.