Abstract
As a preliminary investigation towards obtaining carbon nanotube composite adsorbent for CO2 capture, in this study CO2 adsorption performance of three commercial carbon nanotubes (CNTs) one single-walled carbon nanotubes (SWCNTs), and two (2) different multi-walled carbon nanotubes (referred to as A-MWCNTs and B-MWCNTs) were evaluated and compared. The purpose of this study was to compare the different types of CNTs and select the best to serve as the solid anchor in the development of a hydrophobic composite adsorbent material for CO2 capture. The N2 physi-sorption of the CNTs was conducted to determine their surface area, pore volume and pore size. In addition, morphology and purity of the CNTs were checked with Transmission Electron Microscopy and Raman Spectroscopy, respectively. The CO2 adsorption capacity of the CNTs was evaluated using Thermo-gravimetric analysis (TGA) at 1.1 bar, at operating temperature ranged from 25 to 55 °C and at different CO2 feed flow rates, in order to evaluate the effects of these variables on the CO2 adsorption capacity. The results of CO2 adsorption with the TGA show that CO2 adsorption capacity for both SWCNTs and MWCNTs was the highest at 25 °C. Changing the CO2 flowrates had no significant effect on the adsorption capacity of MWCNTs, but decreasing the CO2 flow rate resulted in the enhancement of the CO2 adsorption capacity of SWCNTs. Overall, it was found that the SWCNTs displayed the highest CO2 adsorption capacity (29.97 gCO2/kg adsorbent) when compared to the MWCNTs (12.09 gCO2/kg adsorbent), indicating a 150% increase in adsorption capacity over MWCNTs.
Highlights
The most common technology to generate electricity is the combustion of fossil fuels in power plants
The surface area obtained for single-walled carbon nanotubes (SWCNTs) was 664.63 m2/g, falling within the range specified in literature
The B-MWCNTs did not display good geometric structure when compared to that of the SWCNTs, but still possess a geometric structure that can be beneficial as a solid anchor in the development of composite adsorbents for CO2 capture
Summary
The most common technology to generate electricity is the combustion of fossil fuels in power plants. Carbon nanotubes are desirable as solid supports in the preparation of composite adsorbents for CO2 capture because they possess very high surface area with good geometric structure that could be used to improve geometric structure of other adsorbents. They are hydrophobic and will not be affected by the presence of water vapour (Ganesh 2013), giving them a unique advantage over other solid sorbents such as zeolites. Extensive research reports on the application of CNTs for CO2 capture are still limited in literature
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
