No abstract

Calcium looping is a promising route for decarbonization of carbon-intensive fossil fuel-reliant industries. Development of sorbents with high CO 2 uptake capacity and cyclic stability is of paramount importance for commercialization of the calcium looping process. In this work, novel CaO-based sorbents stabilized with CaZrO 3 were produced using the solution combustion synthesis method. The effect of using different fuels (citric acid and β-alanine) on the physical properties and the carbon capture performance of the sorbents was investigated. Citric acidsynthesized sorbents indicated a higher surface area (30.0 m 2 /g) compared to β-alanine-derived sorbents (9.3 m 2 /g), resulting in a superior CO 2 uptake capacity. Sorbents were calcined under mild (850 °C, under 100% N 2 ) and harsh (950 °C, under ∼50% CO 2 in N 2 ) calcination conditions in 20-cycle experiments. Under harsh calcination conditions, sorbents exhibited a decreased stability over cycles due to sintering and loss of surface area at high temperatures. The CA20-1x sorbent maintained 96 and 57% of its initial uptake capacity after 20 cycles under mild and harsh calcination conditions, respectively. Sorbents were further spheronized and tested for their uptake capacity and stability. Spheronized sorbents exhibited a reduced uptake capacity under similar testing conditions due to diffusion limitations and a broader uptake rate profile. A longer carbonation time was recommended for spheronized sorbents to improve the uptake capacity.

Carbon capture and utilization/storage is an integral part of a smooth transition to a net-zero energy portfolio. The distinctive advantages of the calcium looping (CaL) process, including low-cost and high-theoretical uptake capacity, make it a promising approach for the decarbonization of fossil fuel power plants and carbon-intensive industries, including cement and steel. CaL exploits the reversible reaction of CO 2 with CaO to capture and release carbon dioxide in a cyclic process. This paper reviews the fundamentals of the CaL process, the kinetics of the carbonation reaction, and extensive research on the development of sorbent materials with high durability for use in the CaL process. Various optimizing strategies for the improvement of the stability and CO 2 uptake capacity of materials are outlined. Lastly, an overview of benchand pilot-scale testing facilities around the world is provided. The characteristics, operating conditions, and the main experimental findings of the testing facilities are summarized.

No abstract

No abstract