Synthesis, Characterization and Application of Amine-Functionalized Hierarchically Micro-Mesoporous Silicon Composites for CO2 Capture in Flue Gas

Abstract

An efficient CO2 adsorbent with a hierarchically micro-mesoporous structure and a large number of amine groups was fabricated by a two-step synthesis technique. Its structural properties, surface groups, thermal stability and CO2 adsorption performance were fully investigated. The analysis results show that the prepared CO2 adsorbent has a specific hierarchically micro-mesoporous structure and highly uniformly dispersed amine groups that are favorable for the adsorption of CO2. At the same time, the CO2 adsorption capacity of the prepared adsorbent can reach a maximum of 3.32 mmol-CO2/g-adsorbent in the actual flue gas temperature range of 303–343 K. In addition, the kinetic analysis results indicate that both the adsorption process and the desorption process have rapid adsorption/desorption rates. Finally, the fitting of the CO2 adsorption/desorption experimental data by Avrami’s fractional kinetic model shows that the CO2 adsorption rate is mainly controlled by the intra-particle diffusion rate, and the temperature has little effect on the adsorption rate.

One-Pot Synthesis of N-Rich Porous Carbon for Efficient CO2 Adsorption Performance

“…Carbon capture and sequestration/storage technologies are considered to play a key role in reducing the emission [ 2 , 3 , 4 ]. Current post-combustion CO 2 capture technologies that have high repeatability and selectivity include the chemical absorption techniques like amine scrubbing [ 5 ], ionic liquid absorption [ 6 ] and the adsorption techniques that use physical adsorbents [ 7 , 8 ] or amine-, lithium- or calcium-based chemical adsorbents [ 9 , 10 ].…”