Carbon Cryogel Preparation via Urea-furfural Gel Synthesis as an Adsorbent for CO2 Capture Application

Adsorption of CO2 using porous solid materials is one of the suitable separation techniques due to its low cost and simple operation. Porous carbon from urea-furfural has been prepared as a potential adsorbent for CO2 capture. In this work, urea-furfural carbon cryogel (CCUF) was prepared using a simple polymerisation reaction under ambient conditions with different water and acid loadings followed by a drying and calcination process. The effect of water and acid loadings on carbon synthesis were evaluated for carbon gel yield and CO2 adsorption performance in a fixed-bed adsorption study. The selected CCUF was characterised with N2 sorption isotherms, CO2 temperature-programmed desorption (CO2-TPD), Fourier transform infrared spectroscopy (FTIR), and focused ion beam-scanning electron microscopy coupled with energy dispersive X-ray (FIBSEMEDX) to understand the carbon surface structure and properties. The CCUF synthesised with 4 mL of water and 0.15 mL of acid loading was selected due to its high CO2 adsorption capacity (2.04 mmol/g) compared to other carbon gels synthesised in this work. The large specific surface area (160 m2/g) of CCUF with high microporosity and nitrogen content provide capabilities for CO2 adsorption under ambient conditions. The result shows that the N-enriched CCUF adsorbent has a potential for CO2 adsorption.