Carbon dioxide adsorption using biomass-based activated carbon functionalized with deep eutectic solvents

The biomass-based activated carbon can be synthesized into green solvent to mitigate disposal problems and enhance production efficiency. The green solvent known as deep eutectic solvents (DES), which exhibits unique characteristics can be used to enhance the performance of the activated carbon and results in high CO₂ adsorption capacity. In this study, new approaches involving the modification of low-cost biomass-based activated carbon with green solvent functionalization agent is proposed. The DES produced will be characterized for their physical properties such as pH, density and viscosity. The modified adsorbents were studied for their surface morphology and element composition using field emission scanning electron microscope and energy dispersive X-ray spectroscopy techniques. Further to this, in order to evaluate the CO₂ adsorption characteristic, breakthrough curve was studied in a packed-bed adsorption reactor. The effects of temperature were used as a parameter for examining the breakthrough time performance. The results revealed that, the breakthrough time decreases with increasing column temperatures. The results indicated that the breakthrough time was longer at a lower adsorption temperature (30°C) for modified activated carbon with DES, which was 5 min. Maximum high adsorption capacity of 11.05 mg/g at lower adsorption temperature was achieved using modified activated carbon with DES.