Journal of Chemical and Petroleum Engineering

Journal of Chemical and Petroleum Engineering

Enhanced COD Reduction of Olefin Plant Spent Caustic Wastewater Using Easily Recyclable Cu(BDC)/MgO Nanocomposites

Document Type : Research Paper

Authors
Soleiman Mosleh 1
Mohammad Mehdi Sabzehmeidani 2
1 Polymer Eng. Dept, Faculty of Gas and Petroleum, Yasouj University, Gachsaran, Iran.
2 Chem. Eng. Dept., University of Science and Technology of Mazandaran, Behshahr, Iran.
10.22059/jchpe.2026.391601.1603
Abstract
This study explored the photocatalytic degradation process for treating industrial spent caustic wastewater, focusing on reducing chemical oxygen demand (COD). Cu(BDC)/MgO nanocomposites were synthesized via microwave-assisted synthesis and served as efficient photocatalysts. An artificial neural network (ANN) model was developed to estimate COD concentrations and optimize treatment parameters, aiming to achieve superior COD reduction. The research aimed to minimize the hydrogen peroxide-to-COD ratio and to optimize other factors influencing COD removal. The synthesized nanocomposites were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), and energy-dispersive X-ray spectroscopy (EDS) elemental mapping. Optimal parameters for achieving a 97.55% COD removal efficiency were identified as a nanocomposite dose of 1.30 g/L, an H2O2/Spent caustic wastewater ratio of 1.50 ml/L, a pH of 3.0, a treatment time of 35 min, and an aeration flow rate of 2.50 L/min. Catalyst recycling studies demonstrated the exceptional recyclability and stability of the Cu(BDC)/MgO nanocomposites, showing they could be reused as catalysts even after five treatment cycles. This highlights the potential for prolonged and sustainable use of these nanocomposites in wastewater treatment processes, effectively reducing COD levels in spent caustic effluents.
Keywords
Artificial Neural Network
Cu(BDC)/MgO Nanocomposites
Chemical Oxygen Demand Spent Caustic Degradation
Petrochemical Effluent
Subjects
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Journal of Chemical and Petroleum Engineering
Volume 60, Issue 1
June 2026
Pages 89-107

  • Receive Date 08 March 2025
  • Revise Date 16 February 2026
  • Accept Date 12 April 2026