Equilibrium Adsorption Study of CO₂ and N₂ on Synthesized Zeolites 13X, 4A, 5A, and Beta

Abstract

This study focused on comprehensive synthesis and analysis for CO 2 adsorption of the widely used zeolites 13X, 4A, 5A, and beta. Zeolites were synthesized utilizing the hydrothermal method. We paid special attention to the characterization of synthesized zeolites. The most common instrumental analysis techniques, including X-ray diffraction (XRD), scanning electron microscopy (SEM), the Brunauer−Emmett−Teller (BET) method, thermogravimetric analysis (TGA), differential thermal gravimetry (DTG), differential thermal analysis (DTA), and X-ray fluorescence (XRF), were utilized in this study. All results indicated the successful synthesis of these types of zeolites. The CO 2 /N 2 system was considered for the investigation of adsorption and separation of CO 2 . The adsorption equilibrium data of CO 2 and N 2 on pelletized zeolites were taken at temperatures of 283, 303, and 323 K and pressures up to 1.6 bar utilizing a volumetric method. The highest adsorption capacity was obtained for zeolite 13X and the lowest for zeolite beta. The Sips and Langmuir isotherm models were used for matching adsorption isotherm data. Experimental data showed the best correlation with the Sips model with six parameters. The isosteric heats of adsorption for CO 2 and N 2 on all the studied adsorbents were evaluated utilizing the pure adsorption isotherms data at studied temperatures by the Clausius−Clapeyron equation. Also, binary adsorption data and selectivities of CO 2 over N 2 on all adsorbents were determined by ideal adsorbed solution theory (IAST). It can be concluded from all the obtained results that the studied zeolites, especially zeolite 13X, can be promising adsorbents to capture CO 2 in practical applications.

CO2adsorption performance of template free zeolite A and X synthesized from rice husk ash as silicon source

“…However, for temperatures above 200 C the mass loss of the zeolite is attributed to the moisture loss which is due to the breaking of hydration complex molecules with exchangeable cations present in the framework of zeolite structure. 25 In the DTG curves shown in Fig. 12(a) and (b) the presence of desorption peak at 135 C for zeolite RA and 335 C for zeolite RX indicate the existence of one type of water graing loss in the framework structure and represents one type of bonding.…”

“…Zeolites are utilized in various elds such as catalysis, gas separation and purication, cation exchange, environmental remediation, food industry, cosmetics, medicine, magnetism and microelectronics. 24,25 One of the most signicant disadvantages of zeolite synthesis procedure is the high cost of the reactants used for their preparation. The silica sources used such as fumed silica, colloidal silica, silicic acid, and silicon alkoxides are environmentally hazardous and expensive.…”

Critical Evaluation of Henry’s Law Constants for Nitrogen on the NaX (13X) Zeolite

“…The Krishnamurthy et al isotherm at 398 K was the low outlier with an A 1 slope of −0.510. The 14 high outliers ranged in value from 0.384 to 3.10. ,,,,− ,− In addition, the two data points at the lowest temperatures (highest values of 1/T) are considered as being overly influential on the regression (they have a high leverage on the fitted line), so they have been excluded from some of the regression calculations.…”

Ion-imprinted modified molecular sieves show the efficient selective adsorption of chromium(vi) from aqueous solutions

“…37 The typical TEM morphology of ZMS-5A is a cubic structure with rounded-off corners. 38,39 When graed with APTES, the shape of ZMS-5A became larger and more irregular (Fig. 3b).…”