Cost and Performance Baseline for Fossil Energy Plants Volume 1: Bituminous Coal and Natural Gas to Electricity

Dual Functional Materials: At the Interface of Catalysis and Separations

“…We illustrate this point with a natural gas combined cycle (NGCC) plant, which produces approximately 4 million kilograms of flue gas per hour. 3 If we achieve a 10% CO 2 capture efficiency, the target CO 2 capture amount is 575 kmol/ h. With a calculated flue gas molecular weight of 28.4 kg/kmol and a cycle time of 1 h with a target adsorption capacity of 5 mmol CO 2 /g DFM, we require approximately 115 t of DFM. If we shorten the cycle time to 15 min and use a DFM with a capacity of 10 mmol CO 2 /g, the required amount of DFM decreases by a factor of 8 to 14.4 t, illustrating that we need DFMs with both high CO 2 adsorption capacity and fast adsorption/reaction kinetics.…”

“…The effect of water is complex, with studies showing that water enhances CaO reactivity with CO 2 , removes coke, and increases pore size, leading to faster diffusion and carbonation . However, during calcination, steam promotes sintering, which decreases the available sites for adsorption, and over many cycles the presence of steam tends to reduce CO 2 capture capacity .…”

“…34 The effect of water is complex, with studies showing that water enhances CaO reactivity with CO 2 , removes coke, and increases pore size, leading to faster diffusion and carbonation. 3 However, during calcination, steam promotes sintering, which decreases the available sites for adsorption, and over many cycles the presence of steam tends to reduce CO 2 capture capacity. 32 An important area of future research is identifying straightforward methods of increasing DFM tolerance to the commonly studied contaminants in flue gas, particularly to those that are not present during typical CO 2 hydrogenation experiments.…”

“…3 NGCC plants are more feasible because sulfur is removed prior to gas combustion, particulate matter is significantly lower than that of coal-fired plants, and the NGCC plants are already equipped with heat recovery systems that may be compatible with DFM technology. 3,4 From our analysis of the literature, it is not completely clear how much heat is available for DFM operation, but the simplest case would be to implement the DFM at the flue gas stack, where the temperature is 80−100 °C. 3 These temperatures are too low for CO 2 hydrogenation, indicating that there is a need for a detailed Aspen study that reports all parameters and considers practical levels of heat recovery to accurately determine the costs associated with running ICCU at a NGCC plant.…”

“…Although methane is the most well-studied product, DFMs have also been explored for producing CO and methanol, as shown in Figure . The reactions and associated enthalpies are listed below, with flue gas compositions taken from DOE and EPA reports. , There are examples in the literature of reducing the bound CO 2 with methane, but these studies are mechanistically more complex and outside the scope of this Perspective …”