Carbon Dioxide Removal From Natural Gas By Using Silica Membrane

The community is already paying high attention to the development of technologies
especially in the natural gas processing. One of the attentions is on the development of
membrane technology in the natural gas separation in order to get high quality of natural
gas. Presence of carbon dioxide contributes to bad effect especially on the corrosion of
equipments, pipelines and this can affect the overall operations. The focus on this
technology is because of several advantages of membranes, such as efficient, simplicity,
high selectivity and permeability, low cost requirement, stability under operating
condition and easy to control leads to the attention of its development.
This project is to synthesize a silica membrane with high performance and high carbon
dioxide/methane (CO2/CH4) selectivity and also to study the effect of pressure, inlet flow
rate and dip coating duration on the separation performance. The silica membrane was
prepared by the deposition of silica sol onto porous alumina support. The experiment
started with the preparation of alumina support and percentage of porosity was
calculated. The highest percentage porosity calculated was 21.89 % by using 20 drops
(1.05 gram) of starch as a binder. Then, alumina support was dipped in the silica
solution. In dip coating method, the times for dipping were varied for 1.25, 2.25 and
3.25 hours and permeability test was conducted. From the calculation, flux increases
when the inlet flow rate and inlet pressure were increased. The highest flux was 1.911
cm3[STP]/cm2.s at 3.5 bar for 50.00 cm3/s inlet flow rate. However, flux decreases as the
dip coating hour increased (also when the silica thickness increases) and flux for carbon
dioxide (CO2) was higher compared to methane (CH4).
The highest permeability was for carbon dioxide (CO2) with 1.009660
cm3[STP].cm/cm2.bar.s at inlet pressure 1.5 bar for 50.00 cm3/s inlet flow rate at 3.25
hours dip coating duration. The separation factor was the highest at 1.5 bar for 50.00
cm3/s inlet flow rate at 3.25 hours dip coating with 1.4212 CO2/CH4 separation factor.