Synthesizing and Characterizing a Mesoporous Silica Adsorbent for Post-Combustion CO2 Capture in a Fixed-Bed System

Abstract

MCM-41, a mesoporous silica with a high surface area and hexagonal structure, was synthesized, and commercial nano-silicon dioxide (SiO2) was used as a solid adsorbed in post-combustion CO2 capture. The CO2 adsorption experiments were conducted in a fixed-bed adsorption system using 5–15 vol.% CO2/N2 at a flow rate of 100 mL/min at varying temperatures (20–80 °C) and atmospheric pressure. Analyses (X-ray diffraction, nitrogen adsorption-desorption isotherms, Fourier-transform infrared spectroscopy, and transmission electron microscopy (TEM)) revealed that the synthesized MCM-41 has mesoporous characteristics: a high surface area and large pore volumes. The CO2 adsorption capacity of MCM-41 and commercial nano-SiO2 increased considerably with increasing CO2 concentration and temperature, peaking at 60 °C. Below 60 °C, dynamics rather than thermodynamics governed the adsorption. Increasing the temperature from 60 to 80 °C decreased the adsorption capacity, and the reaction became thermodynamically dominant. Additionally, compared with commercial nano-SiO2, the MCM-41 sorbent demonstrated superior regenerability and thermal stability.

Improving the estimation accuracy of confined vapor–liquid equilibria by fine-tuning the pure component parameter in the PC-SAFT equation of state

“…Mesoporous and microporous adsorbents have extensive applications, including CO 2 capture, [1][2][3] drug delivery, 4,5 industrial wastewater treatment, [6][7][8] hydrogen production, 9,10 gas dehumidification, 11,12 energy storage, 13 reactions, 14 and catalysts. 15,16 Over the past two decades, considerable advancement has been made in understanding adsorption phenomena and the behavior of confined fluids in porous materials.…”