Desulfurization of light and heavy gas oil from crudes of Kurdistan region-Iraq by oxidation and solvent extraction.

This study analyzes four distinct crude oil varieties from the Kurdistan Region-Iraq: Taq-Taq (TQ), Sarqala (SA), Khurmala (Kh), and Tawke (TA). Fractionation produced five categories: naphtha, kerosene, light gas oil (LGO), heavy gas oil (HGO), and fuel oil. The research focused on distillation cuts of LGO (241–300°C) and HGO (301–360°C), which contained organic sulfur compounds, contributing to environmental pollution and health hazards during combustion. Oxidative desulfurization (ODS) using hydrogen peroxide and acetic acid at 75°C for 12 hours significantly reduced sulfur content. LGO sulfur content decreased from 0.72% to 0.11% wt in SA and from 2.02% to 0.50% wt in TA, achieving desulfurization efficiencies of 84.72% and 74.25%, respectively. In HGO, sulfur content dropped from 3.67% to 1.78% wt in Kh, with 51.49% efficiency. Gas oil recovery after oxidation ranged from 92.71% to 96.28%. Solvent extraction with acetonitrile, methanol, and acetic acid further enhanced desulfurization, with pre-oxidation extraction achieving 19.42% efficiency in LGO, increasing to 86% post-oxidation. Gas chromatography with a flame photometric detector (PFPD) assessed sulfur removal, highlighting the combined effects of oxidation and extraction on sulfur compound reduction. This approach demonstrated the efficiency of ODS in mitigating sulfur-related impacts. [ABSTRACT FROM AUTHOR]