Optimization of CO۲ Capture Process Using Dry Sodium-Based Sorbents

Sodium carbonate (Na۲CO۳) supported by gamma-alumina (g-Al۲O۳) is one of the best sorbents for CO۲ capture in economic terms because of its low raw material cost and excellent performance in low-temperature operation. The fundamental goal of this study is to optimize the operating conditions of CO۲ adsorption by Na۲CO۳/Al۲O۳ sorbent in a fixed bed reactor. The sorbent characterization was studied using BET, SEM, XRF, and XRD analyses, and the sorbent structure was compared before and after the carbonation reaction. Moreover, the effects of side reactions on the adsorption process were investigated. The Response Surface Methodology (RSM) was used with Box-Behnken Design (BBD) to design the experiments. The optimum conditions are introduced at the point where initial CO۲ capture capacity and deactivation rate constants are as high and as low as possible, respectively. The optimum values of the variables corresponding to the temperature of ۵۰°C, vapor pretreatment time of ۹ min, and H۲O/CO۲ mole ratio of ۱. The amounts of initial CO۲ capture capacity and deactivation rate constant in the optimum conditions were obtained to be ۳۹.۲۳۸ mgCO۲/gsorbent and ۰.۴۱۶ min-۱, respectively.

کلیدواژه ها:

CO۲ capture ، Alkali metal carbonate ، Operating parameter optimization ، Response surface methodology (RSM) ، carbonation reaction ، Carbonation kinetics