Development of integrated approach employing Fe/TK)2-[BMIMJFeCl4 system for sulfur removal from model oil

This project researchs onthe development of T1O2 semiconductors doped with Iron, Fe
as the photocatalyst andionic liquid, [BMIMJFeCLt for desulfurization process of model
oil. Current technology for desulfurization requires severe process conditions; high
pressure and temperature in order to remove the sulfur compounds in crude oil.
Therefore, research is being conducted to develop better desulfiirization process
employing photocatalysis andliquid-liquid extraction conducted at atmospheric pressure
and temperature in the presence oxygen. Ti02 was selected as the photocatalyst but not
active in visible light. So, modification was done by doping the Ti02 photocatalyst with
transition metals, Iron, Fe. Transition metal doping is able to enhance the
photoexcitation of electrons in the photocatalyst when only subjected to visible light.
Besides, it can act as charge carriertrapper for both photogenerated electrons and holes
thus inhibiting the electron-holes recombination for longer time. Wet Impregnation
method was chosen to prepare iron-doped catalyst, using h*on(III) Nitrate, Fe(N03)3 as
starting materials. The dopant loading varied from 0.4 to 0.8wt% and two calcination
temperatures were selected which are 400°C and 500°C. Characterization of the
modified photocatalysts were done by X-Ray Diffraction (XRD), UV-vis Diffuse
Reflectance Spectra {UV-vis DRS), Field Emission Scanning Electron Microscopy (FESEM)
and Fourier Transform Infrared Spectroscopy (FTIR). In this project, l-butyl-3-
methylimidazolium tetrachloroferrate , [BMIMJFeCU was preferred as the ionic liquid
for liquid-liquid extraction process as it involved same element with the transition metal
doped to Ti02. [BMIM]FeCl4 was prepared by mixing together anhydrous Iron(IH)
Chloride, FeCl3 and l-butyl-3-methylimidazolium chloride, [BMIM]C1. The
desulfurization analysis using halogen lamp and Gas Chromatography, GCanalysis was
done to investigate the photocatalytic activity of the modified photocatalysts and
extraction process by ionic liquid. It was found that 0.6wt% of Fe/Ti02 calcined at
400°C yield, thus chosen for the integrated approach combining with ionic liquid,
[BMEvflFeCL*. The integrated approach also showed the increment of sulfur removal
from using photocatalyst and model oil alone. The reduction of band gap as a result of
doping was estimated and theinfluence oftheprocess parameters oncatalytic activity is
explained.