Desulfurization of fossil fuel products has grabbed increased attention, where many research themes focus on the synthesis of novel materials with enhanced desulfurization potentialities, at a reasonable cost, and within a shorter working time. So, in this work, we synthesized ultrathin FeOOH nanorods and then anchored them over reduced graphene oxide (FeOOH/rGO nanocomposite) to act as catalyst/adsorbent system during in situ oxidative/adsorptive desulfurization of diesel fuel model. The XRD, FTIR and Raman analyses demonstrated the successful combination of the FeOOH with the rGO surface. The BET surface area of the FeOOH/rGO was enhanced by 2.2 folds compared to the parent FeOOH, with pore volume ~0.268 cc/g. TEM investigation proved the FeOOH-rGO conjugation. The catalytic processes were carried out in association with H2O2 as an oxidizing element in different conditions. FeOOH showed a high adsorption capacity of ~960 mg/g, and obeyed pseudo-second order kinetic confirming chemisorption nature, while
the process Ea recorded about ~85.4 kJ/mol. On the other hand, FeOOH/rGO system achieved ultra-high adsorption capacity of ~989 mg/g with high removal efficiency (98.9%), which assumed FeOOH/rGO as a highly potential catalyst/adsorbent system for ultra desulfurization process.