Applied Chemical Engineering

Desulfurization of heavy naphtha with synthesized active carbon (DPAC) and impregnated (CuCl2): Optimization, kinetic, and isotherm studies

Fatima K.Hamza

College of Engineering, Department of Chemistry, University of Al-Qadisiyah, Al-Diwaniyah, Iraq

Abbas K.Mohammad

College of Engineering, Department of Chemistry, University of Al-Qadisiyah, Al-Diwaniyah, Iraq

DOI: https://doi.org/10.59429/ace.v9i3.6130

Keywords: heavy naphtha; adsorptive desulfurization; DPAC; response surface methodology; kinetics; isotherm models; sulfur removal

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Abstract

This study investigates the adsorptive removal of sulfur compounds from heavy naphtha using phosphoric acid-activated date pit carbon (DPAC) and CuCl₂ impregnated phosphoric acid-activated date pit carbon (CuCl₂/DPAC). The adsorbent was optimized by Response Surface Methodology (RSM) using Box-Behnken Design to study the influence of temperature, contact time, and adsorbent dosage on the sulfur removal efficiency. The optimum conditions led to a maximum sulfur removal efficiency of 71% (31°C, 2.96 hr, and 0.0397 g/mL adsorbent). Kinetic studies revealed that sulfur adsorption followed the pseudo-second-order model, suggesting chemisorption as the adsorption mechanism, and equilibrium data were best fitted with the Freundlich model of adsorption isotherms based on temperature. The research confirms that low-cost biomass-based activated carbon impregnated with CuCl2 is a viable and promising adsorbent to remove sulfur compounds from heavy naphtha, which helps in producing clean fuel and protects the environment.

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