N2 and CO2 Adsorption by Soils with High Kaolinite Content from San Juan Amecac, Puebla, México

Karla Quiroz-Estrada,Lucía López,Efraín Rubio,Roberto Portillo,Miguel Hernández-Espinosa,Fernando Rojas

doi:10.3390/min6030073

Abstract

Carbon dioxide (CO2) is considered one of the most important greenhouse gases in the study of climate change. CO2 adsorption was studied using the gas chromatography technique, while the Freundlich and Langmuir adsorption models were employed for processing isotherm data in the temperature range of 473–573 K. The isosteric heat of adsorption was calculated from the Clausius–Clapeyron equation. Moreover, the thermodynamic properties ΔG, ΔU, and ΔS were evaluated from the adsorption isotherms of Langmuir using the Van’t Hoff Equation. The four soil samples were recollected from San Juan Amecac, Puebla, Mexico, and their morphologies were investigated through X-ray diffraction (XRD) and N2 adsorption at 77 K. The SJA4 soil has a crystalline Kaolinite phase, which is one of its non-metallic raw materials, and N2 isotherms allowed for the determination of pore size distributions and specific surface areas of soil samples. The Barrett–Joyner–Halenda (BJH) distribution of pore diameters was bimodal with peaks at 1.04 and 3.7 nm, respectively. CO2 adsorption showed that the SJA1 soil afforded a higher amount of adsorbed CO2 in the temperature range from 453 to 573 K followed by SJA4 and finally SJA2, classifying this process as exothermic physisorption.

Highlights

Nowadays. one problem that affects our society is the treatment of greenhouse gases, namely, the enforcement of a separation, capture, and storage that is environmentally friendly and economically viable [1], CO2 given that this gas is becoming increasingly important in the future of the world economy [2]
Pore size distribution (PSD) was calculated from the N2 adsorption isotherms through BJH analysis (Figure 3), and the results indicated that
The characterization of soils with high kaolinite content was satisfactorily performed through several experimental techniques; the X-ray diffraction (XRD) results show that the SJA4 soil contains the crystalline kaolinite phase, while, according to N2 adsorption, this same sample attained the highest specific surface area and the widest pore size distribution

Summary

Introduction

Nowadays. one problem that affects our society is the treatment of greenhouse gases, namely, the enforcement of a separation, capture, and storage that is environmentally friendly and economically viable [1], CO2 given that this gas is becoming increasingly important in the future of the world economy [2]. One problem that affects our society is the treatment of greenhouse gases, namely, the enforcement of a separation, capture, and storage that is environmentally friendly and economically viable [1], CO2 given that this gas is becoming increasingly important in the future of the world economy [2]. Carbon dioxide (CO2 ) is considered one of the main greenhouse gases producing global warming. The adsorption processes require the development of new technologies for the effective adsorption and storage of large amounts of CO2 [3]. Carbon sequestration means capturing CO2 from the atmosphere or from anthropogenically produced large-scale mixtures of effluent gases exhausted from industries. Carbon capture involves the separation of this compound from a gas mixture and to adsorb (concentrate) it on the surface of assorted substrates.

Methods

Results

Conclusion