Sodium-Based Dry Regenerable Sorbent for Carbon Dioxide Capture from Power Plant Flue Gas

Dry regenerable sorbent technology is one of the emerging technologies as a cost-effective and energy-efficient technology for CO 2 capture from flue gas. Six sodium-based dry regenerable sorbents were prepared by spray-drying techniques. Their physical properties and reactivities were tested to evaluate their applicability to a fluidized-bed or fast transport-bed CO 2 capture process. Each sorbents contained 20−50 wt% of Na 2 CO 3 or NaHCO 3 . All sorbents except for Sorb NX30 were insufficient with either attrition resistance or reactivity, or both properties. Sorb NX30 sorbent satisfied most of the physical requirements for a commercial fluidized-bed reactor process along with good chemical reactivity. Sorb NX30 sorbent had a spherical shape, an average size of 89 μm, a size distribution of 38−250 μm, and a bulk density of approximately 0.87 g/mL. The attrition index (AI) of Sorb NX30 reached below 5% compared to about 20% for commercial fluidized catalytic cracking (FCC) catalysts. CO 2 sorption capacity of Sorb NX30 was approximately 10 wt % (>80% sorbent utilization) in the simulated flue gas condition compared with 6 of 30 wt % MEA solution (33% sorbent utilization). All sorbents showed almost-complete regeneration at temperatures less than 120 °C.