Experimental Study on CO₂ Capture from Simulated Flue Gas with an Adsorption–Hydration Method

Abstract

As global warming intensifies, it has become urgent to reduce greenhouse gas emissions. In this work, an adsorption− hydration method was employed to separate carbon dioxide (CO 2 ) from simulated flue gas by dispersing 1.0 mol % aqueous tetrahydrofuran solution in activated carbon, which resulted in the formation of hydrates. The hydrate phase equilibrium data was measured for determining the appropriate operating conditions. Four activated carbons (1 # , 2 # , 3 # , and 4 # ) with different particle sizes were used as dispersion media under the condition of the same water content. Wet activated carbon 2 # (50.0 wt % water content) showed the best performance. After separation, the CO 2 concentration in equilibrium gas phase decreased from 20.86 to 3.07 mol %, and its recovery reached 90.35% at 274.15 K and 2.302 MPa. Then, the effects of water content and initial gas−solid ratio were examined. The results demonstrated that the variations in water content within the range 20.81−60.43 wt % had almost no effect on the adsorption process at 274.15 K and an initial pressure of 3.5 MPa. However, excess water lowered the hybrid separation efficiency. At a certain water content, there existed an optimum initial gas−solid ratio, which was favorable for CO 2 recovery. The recycling of wet activated carbons was conducted, and the results indicated that their working capacities did not change after recycling. This study contributes to better understanding of CO 2 capture from flue gas with an adsorption−hydration method and also offers the optimization of an adsorption−hydration process.

Molecular Dynamics Simulations of the Stability and Dissociation of Structure-H Clathrate Hydrates in the Presence of Different Amino Acids, Gas Species, and sH Hydrate Formers

“…Such methodologies can also be used for wastewater treatment, e.g., removing salt ions and effluent concentration . Also, introducing viable hybrid approaches including hydrate formation–dissociation stages with more efficiency than their standalone utilizations have been newly developed. − Moreover, different gas species can be stored within the crystalline structures of the hydrates, which make them a potentially attractive option for storage and transportation. The use of gas hydrates for gas storage has several advantages over traditional methods, including a suitable storage capacity, low environmental impact, and low cost .…”

Molecular Dynamics Simulation Studies on the Stability and Dissociation of Clathrate Hydrates of Single and Double Greenhouse Gases

“…21 These technologies in comparison with conventional methods possess some advantages, for example, moderate operation conditions, simple process, and high environmental compatibility. 22 Somewhat more recently, to eliminate the remaining CO 2 and improve the CO 2 recovery, hybrid methods such as the combination of hydratemembrane, 23 hydrate-cryogenic, 24 hydrate-absorption, 25 and hydrate-adsorption 26 methods have been designed. The process of capturing/separating GHGs can be followed by hydrate-based GHG utilization.…”