Carbon capture has been a highly sought-after technology for decades because of its<br/>capabilities to restore atmospheric damage done by greenhouse gasses. Thanks to evolving<br/>separation techniques, carbon capture is becoming more efficient with every new discovery in<br/>the field. Currently the biggest problems that carbon capture are facing is the cost of<br/>manufacturing material to aid the process and obtaining ideal conditions for removal of carbon<br/>from air and devising solutions for removal of CO2 in ambient and flue gas conditions.<br/>This Honors Thesis is a continuation of Dr. Shuguang Deng and Dr. Mai Xu’s research<br/>initiative to manufacture and test various zeolitic CO2 removal efficiencies. The goals of this<br/>Honors Thesis are to investigate the adsorption/desorption kinetics and isothermal equilibrium<br/>CO2 capacity of a NaX nanozeolite under ambient air conditions.<br/>What was determined from the following testing was that the zeolite of interest had a<br/>higher adsorption capacity of CO2 at lower temperatures, had a maximum equilibrium quantity<br/>adsorbed of 0.203 mmol/g for CO2 and 0.367 mmol/g of N2, had a maximum breakthrough CO2<br/>capacity of 0.101 mmol of CO2 per gram of zeolite at dry conditions and 298.15K and this<br/>linearly decreased to 0.040 mmol/g at 25% relative humidity.
A perovskite oxide material, La0.1Sr0.9Co0.9Fe0.1O3-δ (LSCF1991), was investigated first for high-temperature air separation. The oxygen sorption/desorption behavior of LSCF1991 was studied by thermogravimetric analysis (TGA) and fixed-bed breakthrough experiments. A parametric study was performed to design and optimize the operating parameters of the high-temperature air separation process by pressure swing adsorption (PSA). The results have shown great potential for applying LSCF1991 to the high-temperature air separation due to its excellent separation performance and low energy requirement.
Research on using nanostructured zeolite NaX (NZ) as adsorbents for CO2 capture was subsequently conducted. The CO2/N2 adsorption characterizations indicated that the NZ samples lead to enhanced adsorption properties compared with the commercial zeolites (MZ). From the two-bed six-step PSA simulation, NZ saved around 30% energy over MZ for CO2 capture and recovery while achieving a higher CO2 purity and productivity.
A unique screening method was developed for efficient evaluation of adsorbents for PSA processes. In the case study, 47 novel adsorbents have been screened for coal bed methane (CBM) recovery. The adsorbents went through scoring-based prescreening, PSA simulation, and optimization. The process performance indicators were correlated with the adsorption selectivity and capacities, which provides new insights for predicting the PSA performance.
A new medium-temperature oxygen sorbent, YBaCo4O7+δ (YBC114), was investigated as an oxygen pumping material to facilitate solar thermochemical fuel production. The oxygen uptake and release attributes of YBC114 were studied by both TGA and a small-scale evacuation test. The study proved that the particle size has a significant effect on the oxygen pumping behavior of YBC114, especially for the uptake kinetics.