Characterization of the modified photocatalysts was done by X-ray diffraction (XRD), UV-vis diffuse reflectance spectrum {UV-vis DRS), field emission scanning electron microscopy (FE-SEM) and transform infrared spectroscopy Fourier (FTIR). Summary of EDX result for pure Ti02 Summary of EDX result for Fe/Ti02 Summary of desulfurization experiment result. This project is researching the use of photocatalyst, semiconductor as an oxidizing agent of sulfur compound in model oil through photocatalytic oxidation.
Interest in the photocatalytic oxidation process is focused because of the process condition, which is immoderate, in addition to the presence of light. Research was carried out on the photocatalyst with the aim of understanding the fundamental photoelectrochemical process, its feasibility and improving the photocatalytic efficiency of the semiconductor. The empty region extending from the top of the filled valence band to the bottom of the empty conduction band is called the band gap.
Due to the low photo-quantum efficiency of Ti02] recombination of the photo-excited electron-hole pair must be delayed for an efficient charge transfer process to occur on the photocatalyst surface. In this illustration, the energy levels of the bulk and surface state traps fall within the band gap of the semiconductor. The release of the oxygen radical will further initiate the photocatalytic reaction (Tianzhong T., et al.
As far as the project is concerned, [BMEvflFeCU is used as it uses the same doping metal element, iron, Fe.
Integrated System ofPhotooxidation - Ionic Liquid Extraction Approach
So the extraction of sulfur compounds occurs simultaneously with the extraction of oxidized sulfur compounds. The decrease in the concentration of sulfur compounds in the model oil is caused by the oxidation of sulfur compounds in the phase of the model oil and its extraction in the ionic liquid phase by polar attraction. The effect of transition metal doping and the concentration of doped Fe will affect the modified photocatalytic activity.
This change in concentrations was made to observe the dependence of photocatalyst performance on the amount of dopant. Photocatalyst characterization is an essential process for determining the physical properties of a photocatalyst. This test is performed to determine the phases, crystal structures and crystallite sizes of the modified TiO2 photocatalyst.
A desulfurization experiment was carried out to observe the photocatalytic capabilities of Fe/Ti02 photocatalysts and the extraction process with [BMIM]FeCLi for sulfur removal in model oil. A sample of the model oil is taken at the beginning and at the end of the experiment. The samples are analyzed by GC (Gas Chromatography) analysis to determine the amount of sulfur remaining in the model oil.
The GC Analyzer uses the area under the peak of the curve from the sample to calculate. All the prepared photocatalysts were subjected to XRD analysis and the test result presented by XRD diffractography of the samples is shown in Figure 4.2. These results support that the current doping procedure allows uniform distribution of dopants, forming stable.
The DR-UV-Vis spectra of the catalyst samples as well as of pure TiO 2 are depicted in Figures 4.3 and 4.4 (zoomed to be between wavelengths of 350 to 550 nm). When doped with Fe, there was a significant shift of the peak towards the visible region at about 400-800 nm for all the samples as shown in clearer image in Figure 4.4. The UV-Vis absorption edge and band gap energies of the samples have been determined from the reflectance [F(R)] spectra using the KM (Kubelka-Munk) formalism and the Tauc plot.
Where hv = photon energy, e.g. = the band gap energy, and K = a constant characteristic of the semiconductor material. The extrapolation of the corresponding graph also shows that the calculated band gap energy for pure TiO2 is 3.25 eV.
FeTiO400 j
But at 100K magnification, the scan is not sufficient to observe the dopant distribution in the supported Ti02 as no real difference is shown in the morphological results. As shown in the EDX results of Table 4.2 and 4.3 (a)-(f), the Fe metal concentration in Ti02 is analyzed from the elemental analysis, and the result shows that Fe is present in Fe/Ti02, but the calculated values are slightly different. as target values. As for the samples after calcinations, the FTIR spectra of the samples are shown in Fig.
The desulfurization process represents the observation in the sample of photocatalysts (pure Ti02 and Fe/Ti02) regarding the improvement of the photocatalytic activity of the modified photocatalysts and the extraction process from the ionic liquid, [BMIMJFeCU- All 7 photocatalyst samples were used in the experiment of desulfurization. , plus an ionic liquid, [BMIMJFeCU, tested one by one before the best among the tested photocatalysts is taken to combine with [BMIMJFeCU as integrated approach for desulfurization process. As the methodology specified in the previous section, samples were taken at the beginning and end of the experiment. The results show that the desulfurization process, from the results model, the percentage of sulfur removal increases from Fe/Ti02 concentration of 0.4 to 0.6 wt% and decreases from 0.6 to 0.8wt%.
The results show that the desulfurization process from the pattern of results, the percentage of sulfur removal increases from Fe/Ti02 concentration of 0.4 to 0.6 wt% and decreases from 0.6 to 0.8 wt%. Furthermore, the photocatalytic activities of the produced photocatalysts decrease with increasing calcination temperature. Doping of Fe3+ has been confirmed as responsible for the reduction of photo-.
As the calcinations increase, the temperature will cause the morphology of the photocatalyst to change, resulting in a reduction of the particle contact area. The desulfurization of Fe/Ti02 is much higher than that achieved with pure Ti02 alone. Furthermore, the desulfurization of Fe/Ti02 samples calcined at 400°C is higher than that calcined at 500°C, indicating that the photocatalytic activity of the photocatalyst depends on the amount of dopant and calcination temperature.
Of the seven photocatalyst samples prepared, (Ti02 and Fe/Ti02) Fe/Ti02 with 0.6 wt% Fe calcined at 400°C exhibits the best sulfur removal percentages at 7.14% sulfur removal, thus selecting for to be combined with the ionic liquid as an Integrated System. The size range of particle sizes for pure Ti02 and Fe/Ti02 catalyst varied between 20 and 50 nm. For future studies and improvements, more characterization method should be done for in-depth studies of photocatalyst properties using Brunauer Emmett Teller specific surface area (BET), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM) ), thermogravimetric. Analysis (TGA), Temperature Programmed Reduction (TPR) and Atomic Absorption Spectrometry (AAS).
Modification should be performed on the method for the preparation of modified photocatalysts to optimize the distribution of the dopant in supported TiO 2 . Investigation of the desulfurization process should be carried out by other sulfur species such as benzothiophene, and instead of using model oil, the reaction should be continued using the crude oil so that real efficiency of desulfurization by both photocatalytic desulfurization and extraction can be observed. 1998), TiO2 photocatalytic oxidation of selected heterocyclic sulfur compounds, Journal of Photochemistry and Photobiology A: Chemistry.
