Mineral Carbonation of Red Gypsum for CO₂ Sequestration

Abstract

Reduction of carbon dioxide (CO 2 ) emissions into the atmosphere is a key challenge to mitigate the anthropogenic greenhouse effect. CO 2 emissions cause lots of problems for the health of humans and increase global warming, in which CO 2 uptake decreases these environmental issues. The mineral carbonation process is an alternative method during which industrial wastes rich in calcium (Ca) or magnesium (Mg) react with CO 2 to form a stable carbonate mineral. In this research, the feasibility of CO 2 mineral carbonation by the use of red gypsum, as a Ca-rich source, was evaluated using an autoclave mini reactor. Wide-range conditions of procedure variables, such as reaction temperature, reaction time, CO 2 pressure, and liquid/ solid ratio, on the rate of mineral carbonation were studied. The results showed that the maximum conversion of Ca (98.8%) is obtained at the condition that has an optimum amount of these variables. Moreover, the results confirmed that red gypsum has high potential to form calcium carbonate (CaCO 3 ) during the process of CO 2 mineral carbonation. It was concluded that the mineral carbonation process using red gypsum can be considered to be an interesting, applicable, and low-cost method in industry to mitigate a considerable amount of CO 2 from the atmosphere, which is the main issue in the current and coming years.

Synthesis of Magnesium Carbonate via Carbonation under High Pressure in an Autoclave

“…Direct CO 2 sequestration at high pressure with olivine as a feedstock has already been performed in numerous studies at different temperatures and pressures with or without the use of additives such as carboxylic acid, and sodium hydroxide [11,12]. It is reported that optimal reaction conditions are in the temperature range of 150-185 • C and in the pressure range of 135-150 bar [10]. Additives are reported to have a positive influence on carbonation rate.…”

“…Red gypsum usually exists in the form of calcium sulfate dihydrate (CaSO 4 •2H 2 O). Typically, red gypsum has a purity of 95% and has large resources in Malaysia [10]. Due to the large calcium content its carbonation is also a promising CCS option, i.e., one ton of red gypsum can stably bind 0.26 tons of gaseous CO 2 .…”

Synthesis of Nanosilica via Olivine Mineral Carbonation under High Pressure in an Autoclave

“…Direct CO 2 sequestration at high pressure with olivine as a feedstock has already been performed in numerous studies at different temperatures and pressures with or without the use of additives such as carboxylic acid, and sodium hydroxide. It is reported that optimal reaction conditions are in the temperature range of 150-185 • C and in the pressure range of 135-150 bar [15]. Additives are reported to have a positive influence on carbonation rate, but without a study in detail.…”

Production of Methanol from Aqueous CO2 by Using Co3O4 Nanostructures as Photocatalysts

“…Almost all the excess of this gas in the atmosphere is produced by the combustion of mineral fuels, like gasoline or coal. Many efforts have been done in the last years aiming to reduce CO 2 emissions to the atmosphere: imposition of taxes for CO 2 emissions, CO 2 sequestration using different methods [10][11][12][13][14][15][16][17][18][19][20], or the conversion of this gas using different techniques to obtain value added products, e.g., fuels [21][22][23][24][25][26][27][28][29][30][31][32][33]. In order to reduce CO 2 quantity in the atmosphere and produce fuels using this gas and water, different materials and methods have been applied: metal complexes [21], microalgae [28,33], syngas procedure [24], polymers [31], electrochemical transformations [26,32], photothermal and thermochemical conversions [23,25], semiconductors [27,30], and several others.…”