فرزانه قاسم خواه مشكله

   Abstract Oxidative desulfurization (ODS) is a promising method for replacing the traditional hydrogenation desulfurization process. High selectivity in removing refractory organic sulfur compounds, low cost, and milder operating conditions are the most important advantages of this desulfurization method, which has attracted the attention of many researchers in recent decades. In this research, a 3%Mn-15%MoO3/?-Al2O3 bimetallic catalyst along with H2O2 as an oxidizing agent and DMF as a solvent were used to remove organic sulfur compounds by oxidative desulfurization. For this purpose, the mesoporous 3%Mn-15%MoO3/?-Al2O3 catalyst was synthesized using the wetness impregnation method. The synthesized catalyst was characterized using XRD, FTIR, FESEM, EDS-MAPP, and BET tests, showing that the catalyst with 15%Wt MoO3 (as the active metal) and 3%Wt Mn (as the promoter metal) exhibited the best performance for oxidative desulfurization. Subsequently, the operating conditions were optimized using Design Expert 11 software and the CCD(central composite design) method to achieve the highest desulfurization efficiency. The highest desulfurization efficiency was achieved at an O/S molar ratio of 3.4, a catalyst loading of 1.1 grams for 3%Mn-15%MoO3/?-Al2O3, a reaction temperature of 60.2°C, and a reaction time of 30 minutes. Additionally, under these optimized conditions, the ODS process was performed on sour gas oil and fuel oil cuts produced by the Lavan oil refinery, resulting in desulfurization efficiencies of 58% and 44%, respectively. These efficiencies were expected due to the higher concentration and complexity of sulfur compounds present in these cuts. Finally, the 3%Mn-15%MoO3/ ?-Al2O3 catalyst underwent five regeneration cycles, and the results demonstrated that the catalyst maintained its activity well and can be reused after five regeneration cycles.    Keywords: desulfurization, Oxidative desulfurization, Bimetallic Catalyst, Wetness Impregnation,   Modeling And Optimization.   

  In this study, the effects of various pretreatment methods on cellulase enzyme production from wheat straw using solid-state fermentation and the fungus *Trichoderma reesei* ATCC 26921 were investigated. Wheat straw, as a significant agricultural waste in Iran, has high potential for producing industrial enzymes and bio-products. The main objective was to find the optimal pretreatment method for maximizing cellulase production. Through Box-Behnken design, the best fermentation conditions were found at 30°C, 80% humidity, over 6 days. The study explored acidic, alkaline, combined, and deep eutectic solvent pretreatments, revealing that the deep eutectic solvent calcium carbonate-glycerol improved enzymatic activity by 38% compared to untreated samples. FTIR analysis showed enhanced lignin and hemicellulose degradation, improving cellulose accessibility. This research emphasizes sustainable development and optimal use of agricultural waste, offering new pathways for industrial enzyme production and reduced environmental pollution.