Immobilized Acidic Ionic Liquids:Synthesis,Characterization And Their Application In Desulfurization

Improvement of industrialized hydrodesulfurization and development of non-hydrodesulfurization have been steped up, in order to meet the new standards for sulfur content in the fuel oil. In the non-hydrodesulfurization, photochemical desulfurization is a novel method, which is easy to control and save energy, etc.（1） In this paper, Immobilized acidic ionic liquids were firstly synthesised by grafting method, they were denoted as X%-ILs@SBA-15. Modern instrumental analysis methods such as HPLC、FT-IR、TG and elemental analysis were applied to characterize the physical and chemical properties of immobilized acidic ionic liquids. The influencing of oxidation extraction desulfurization performance on model oil by immobilized acidic ionic liquids catalyst was conducted. The catalyst combined the hydrophilic of carrier and the lipophilic of acidic ionic liquids, showing better performance of catalytic desulfurization. Results showed that the optimum reaction conditions for the reaction system: catalyst dosage: 1% of model oil quality; volume ratio of acetonitrile to model oil: 1; O/S molar ratio: 10; reaction temperature: 333 K; reaction time: 60 min. Under above conditions, the Dibenzothiophene（DBT） removal of model oil was 82%, Benzothiophene（BT） was 85% and Thiophene（T） was 88%. GC-MS and FT-IR of oxidation products revealed that the products were mostly transformed into dibenzothiophene sulfone. The catalyst showed better performance of recycling and the activity can still reach 72% after using four times.（2） Then photocatalysts were synthesised by impregnation method, they were denoted as DCQ-X%Ti O₂/SBA-15. Modern instrumental analysis methods such as XRD、HPLC、Raman、FT-IR and BET were applied to characterize the physical and chemical properties of photocatalyst. The influencing of photocatalytic oxidation desulfurization performance on model oil by photocatalyst was conducted. After loading the DCQ molecular, the photocatalysts can broaden spectral response range and used the light from the sun more effectively, benefiting photocatalytic oxidation desulfurization of model oil. Results showed that the optimum reaction conditions for the reaction system: catalyst dosage: 0.45% of model oil quality; 10 m L of acetonitrile; O/S molar ratio: 15; reaction temperature: 293 K; reaction time: 180 min. Under above conditions, the DBT removal of model oil was 85%, BT was 89% and T was 93%. Also, GC-MS and FT-IR of oxidation products revealed that the products were mostly transformed into dibenzothiophene sulfone. The catalyst showed better performance of recycling and the activity can still reach 70% after using four times.