Vol. 1 No. 1 (2025)

Articles

Smart Electrodes Enhanced by Machine Learning: Revolutionary Cadmium Extraction from Phosphoric Acid Using Moringa-Enhanced Carbon Sensors

Published 2025-06-15

  • Imane Chtaini
    • ,
  • Mustapha Oukbab
    • ,
  • Abdelilah Chtaini

Imane Chtaini
Independent Researcher, Casablanca 20000, Morocco

Mustapha Oukbab
Faculty of Science and Technologies, Sultan Moulay Slimane University, Béni Mellal 23000, Morocco

Abdelilah Chtaini
Faculty of Science and Technologies, Sultan Moulay Slimane University, Béni Mellal 23000, Morocco

DOI: https://doi.org/10.64797/rwas.v1i1.28

Abstract

This study presents a comprehensive electrochemical investigation of cadmium removal from 54% phosphoric acid solutions using Moringa oleifera-modified carbon paste electrodes (CPE) in sodium chloride medium. The research employed advanced machine learning analytical techniques to optimize electrode performance and characterize the removal mechanisms. Cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and square wave voltammetry (SWV) were utilized to evaluate the electrochemical behavior of cadmium in the presence of Moringa-modified electrodes. The machine learning-optimized system demonstrated superior performance compared to traditional methods, achieving processing speeds exceeding 10,000 units with enhanced sensitivity and detection capabilities. Principal component analysis revealed three distinct mechanistic clusters: protonation, complex formation, and surface effects. The Moringa-modified electrodes showed excellent correlation (R² > 0.998) between experimental and machine learning-predicted values in Tafel analysis, with cadmium detection accuracy reaching 98.8%. Feature importance analysis identified Moringa particle size, surface roughness, and ionic strength as the most critical parameters influencing removal efficiency. The optimized frequency range of 27.3 Hz provided maximum signal-to-noise ratio and sensitivity. These findings demonstrate the potential of machine learning-enhanced, bio-modified electrodes for efficient heavy metal removal from industrial phosphoric acid solutions.

Keywords

Cadmium Removal, Phosphoric Acid, Moringa Oleifera, Carbon Paste Electrode, Electrochemical Impedance Spectroscopy, Machine Learning, Heavy Metal Detection, Biosorption

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