Document Type : Research Paper

Authors

• Farshid Kazemi ¹
• Hasan Ali Zamani ¹
• Mohamad Reza Abedi ²
• Mahmoud Ebrahimi ¹

¹ Department of Applied Chemistry, Mashhad Branch, Islamic Azad University, Mashhad, Iran

² Department of Applied Chemistry, Quchan Branch, Islamic Azad University, Quchan, Iran

Abstract

Methadone is a synthetic drug utilized to manage chronic pain and treat opioid maintenance. The drug enters water bodies as a contaminant due to its widespread use in various communities, which is usually not removed by wastewater treatment plants. Therefore, a photodegradation procedure was developed to degrade and remove methadone in water samples. A hydrothermal strategy was applied to prepare three photocatalysts based on Cr₂O₃ nanoparticles, a polyoxometalate (phosphotungstic acid), and a hybrid material (Cr₂O₃ nanoparticles encapsulating phosphotungstic acid). The effective factors, such as methadone concentration, pH, photocatalyst amount, and H₂O₂ concentration, in the photodegradation method for each catalyst were optimized by an experimental design using a central composite design. Under the optimum conditions, the kinetic model and maximum photodegradation efficiency of the process for each catalyst were studied to compare their ability for methadone degradation. The maximum photodegradation efficiencies for methadone degradation using phosphotungstic acid and Cr₂O₃ nanoparticles were 82.00 and 77.18% for 120 min. In comparison, the maximum photodegradation efficiency in the presence of Cr₂O₃ nanoparticles encapsulating phosphotungstic acid was 90.11% for 100 min. The results indicated the new hybrid material prepared from encapsulating phosphotungstic acid with Cr₂O₃ nanoparticles, leading to a proper increase in the methadone degradation and reducing the degradation time significantly. 

Graphical Abstract

Keywords

• Methadone
• Cr2O3
• Hydrothermal synthesis
• Hybrid material