Desulphurization of Model Oil using Immobilized [BMIM]FeCL.

INTRODUCTION

Introduction

Ionic liquids have become one of the choices in daily activities, since its unique properties such as negligible vapor pressure, low toxicity, high chemical and thermal stability and ability to dissolve in the many types of organic and inorganic compounds. Due to the special properties, Ionic Liquids can be used in many applications such as synthesis, catalysis and separation.

Understanding Ionic Liquid

Desulphurization using Ionic Liquid

However, problems arise due to difficulty in separating the ionic liquid from the crude oil. However, ionic liquid can be immobilized on a solid to overcome the separation issue between the ionic liquid and the crude oil. To anchor an ionic liquid to a polyelectrolyte, a carboxyl-terminated ionic liquid (IL-COOH) is synthesized.

The purpose of this experiment is to immobilize the ionic liquid, which is [BMIM]FeC4, on the PSF through the spray suspension dispersion. Later, the produced ionic liquid will be tested using SHIMADZU Fourier Transform Infra-Red (FTIR) Spectrometer and S-4800 HITACHI Field Emission Electron Microscope (FESEM) to characterize the component as [BMIM]FeC4. The water is used to wash the remaining dichloromethane to produce the immobilized ionic liquid.

However, the oil phase will solidify faster and produce a relatively larger lump of immobilized ionic liquid. After immobilized ionic liquid is produced, the ability to extract sulfur from the model oil is tested. Referring to Figure 4-1, the water is added to [BMIM]FeC4 and the result shows that the water and the ionic liquid are not completely mixed.

However, when the ionic liquid is exposed to air, the round shape breaks and becomes a layer of polymer. Another possible substance that may have ionic liquid in the oil phase deposition is the dichloromethane-insoluble slip substance. In sample 11 _ 4 and IL _5, desulfurizations give positive results where the ionic liquid can desulfurize the model oil.

This may be due to the addition of PSF in the mix, causing the model oil to ionic liquid ratio to vary greatly. As for the difference in results between IL_8 and IL_9, this is due to the different form of immobilized ionic liquid. Thus, this indicates that IL immobilization can also increase the separation efficiency of the ionic liquid.

Field emission scanning electron microscopy (FESEM) is used to analyze the microscopic composition of the immobilized ionic liquid. This indicates that the PSF is able to fix the ionic liquid on it and does not let it mix with the model oil after rigorous mixing.

Table 2-1 Desulphurization ofDBT in various molar ratio ofFeCI3/[BMIM]CI

Immobilization of Ionic Liquid

Chemicals and Apparatus

Synthesis of [BMIM]FeCL,

Immobilization of [BMIM]FeCL, onto polysulfone (PSF)

The experiment is repeated by desulfurizing the model oil using a 1:5 weight ratio of [BMIM]FeC14 to model oil. After [BMIM]FeC4 is produced in batch, the component must be tested first to check if it is the ionic liquid required. Pieces of the fabric are taken out little by little and put in the water.

Although the ionic liquid is reduced by half, the desulfurization rate is more than half of the initial efficiency, which is about 60%. Water comes during the solidification process of the liquid mixture of [BMIM]FeC4, PSF and dichloromethane. It can show that IL immobilization exhibited better performance compared to that using only ionic liquid.

Figure 4-1 Figure showing different result from mixing ionic liqnid with model oil The sulphur contents of the extracted oil tested monitored using XRF

Desulphurization of model oil using innnobilized [BMIM]FeCL,

Desulphurization of model oil .................................................................................. l2

Comparison of the sulfur content before the extraction will provide the extraction efficiency of the immobilized [BMIM]FeC4. After passing the SSD, the mixture was slimy and not completely solid, as seen in Figure 4-2. The experiment is repeated, but with different amounts of [BMIM]FeC4 (6g), PSF (6g) and DCM (80ml).

The results show that there is still some left, but only a small amount this time. The experiment continues by spraying the oil phase solution into the aqueous phase solution. After immobilizing the IL on the PSF via SSD, the IL is tested in solid form using 2 wt"/o BT in dodecane.

However, as mentioned above, the 1:1 ratio by weight of model oil to immobilized IL actually takes into account the combination of IL and PSF.

Figure 4-2 Insoluble component that is not dissolved in the mixture

FTIR characterization results

The liquid mixture is sprayed into water and the water will wash away the dichloromethane and cause the mixture to solidify. However, during the process, there may be a possibility that water is trapped in the solid compound resulting in the strong 0-H stretching band of 3500 em·'.

FESEM characterization results

BMIM]FeC4 is a good IL option for desulfurization agent giving 97% sulfur removal (lg IL : lg model oil). A FeCb/[BMIM]Cl ratio of 1 gives the best extraction based on the oil model specifications given previously. Due to limited resources for the project, some experiments cannot be done in perfect condition.

For example, the nozzle currently used for the experiment has a large pore size of about 1 Omm. The experiment is assumed to be performed with a smaller pore size nozzle, i.e. a pore size of about 0.1 mm. Be careful not to be exposed to air during the reaction, as this will allow both ionic liquids to react with water vapor.

Add the [BMIM]FeCI4 to the model oil at room temperature (at a weight ratio oil/IL of 1) in a test tube. Prepare aqueous phase storage by mixing 2g gelatin in 100ml deionized water with constant stirring. A spray nozzle is installed to bring the fluid from oil phase storage to water phase storage.