Aqueous two-phase systems based on choline chloride/urea and betaine/urea deep eutectic solvents show improved effectiveness for separating heavy metals from industrial wastewater, particularly hexavalent chromium, which is well known for its toxicities.
Research conducted by Sadeghi and Pazuki highlights the importance of these systems, which offer environmentally friendly alternatives to traditional heavy metal extraction methods. The study indicates significant results with the betaine/urea system showing superior extraction efficiencies under specified conditions.
Heavy metals like chromium present considerable risks to human health and the environment due to their toxicity and persistence. Industrial effluents often contain hazardous metal ions, particularly hexavalent chromium, which is classified as carcinogenic by the Environmental Protection Agency (EPA). Effective removal or separation of these toxic substances is necessary to mitigate health risks and environmental damage.
This innovative research utilizes aqueous two-phase extraction systems formed by mixing deep eutectic solvents and dipotassium hydrogen phosphate salt. These systems demonstrated effective performance and could play significant roles in wastewater treatment approaches. The study tested various parameters, including temperature, pH, metal ion concentration, and salt composition, to optimize the extraction processes.
The results indicated extraction efficiencies of 86.82% for the system utilizing choline chloride/urea at optimal conditions of pH 10 and temperature of 25 °C, whereas the betaine/urea based system achieved even higher efficiency at 89.51% under pH 8.9 and similar temperature settings.
Both systems effectively separated hexavalent chromium from various industrial wastewater matrices, with the researchers noting their potential applicability for other heavy metals such as lead, cobalt, nickel, and cadmium. These findings point toward significant improvements over existing methods, which are often expensive and environmentally damaging.
Notably, the research emphasizes the advantage of using the betaine/urea system, highlighting its broader phase separation range and compatibility with biological compounds, greatly contributing to its potential utility as part of green chemistry strategies.
Overall, the study by Sadeghi and Pazuki not only advances the methodologies used for heavy metal separation but poses remarkable possibilities for addressing industrial pollution challenges.