Carbonation Characteristics of Isolated Calcium Oxide Nanoparticles for Thermal Energy Storage

Carbonation of lime is an attractive system for thermal energy storage. The typical use of 10-m particles creates well-known recycling problems. We propose the use of isolated nanoparticles dispersed over a high surface area to avoid sintering and model the conversion time characteristics of such particles. Our calculations show that reactions on the surface dominate in particles smaller than 70 nm, leading to fast conversion times. We compare our predictions against experimental data on micrometer- and nanometer-size particles to establish the validity of the model. This work shows that isolated nanoparticles arranged in scaffolds are an ideal system for realizing fast and repeatable conversion for thermal storage with high storage density.