Carbon Dioxide Mineral Carbonation Through pH-swing Process: A Review

Abstract

The promotion of carbon dioxide (CO2) reduction methods is due to the fact that the CO2 concentration has been increasing rapidly in 21 st century. In order to prevent further damage of the environment caused by greenhouse gases, CO2 concentration should be stabilized by increasing CO2 fixation, which can reduce CO2 emission into the atmosphere. M ineral carbon sequestration or mineral carbonation is the process of utilizing minerals, mostly rich in calcium and magnesium (Ca/M g) as the feedstock in reaction with CO2 to produce stable solid carbonates. M ineral carbonation through indirect pH swing process is a very effective method for producing calcium and magnesium carbonates. The Ca/M g ions are extracted out of feedstock using suitable solvents at low pH condition and then in the second step the leached Ca/M g ions are carbonated at elevated pH condition. In this paper the state-of-the-art of the carbonation involving pH swing method is updated. Introducti onFossil fuels by providing mo re than 86% of the world energy are the main energy sources in the world. Co mbustion of these huge amounts of fossil fuels emit g reenhouse gases (GHGs) and in particu lar carbon dio xide (CO2) into the at mosphere. Continuous increment of g lobal CO2 due to co mbustion of fossil fuels leads to steady rise of global mean temperature. These activit ies have resulted in increasing the CO2 concentration fro m 280 pp m in the 1750s to 398 ppm in 2013. As a consequence, the global climate has

Mineralization of Carbon Dioxide: A Literature Review

“…Azadarpour et al [201] reviewed the mineral carbonation with minerals rich in calcium and magnesium, via pH swing process for the formation of calcium and magnesium carbonates.…”

Indirect mineral carbonation of chlorinated tailing derived from Ti‐bearing blast‐furnace slag coupled with simultaneous dechlorination and recovery of multiple value‐added products

“…This method also suffers from low value‐added products. Indirect carbonation ordinarily consists of two successive steps: extraction of Ca and Mg from the materials with an acidic or weakly acidic additive and carbonation of the extracted Ca and Mg with CO 2 in a basic or weakly basic environment . Researchers are increasingly examining indirect carbonation because of its relatively mild reaction conditions, high carbonation ratio, and valuable products.…”

“…The feedstock for mineral carbonation includes Ca‐ and Mg‐rich natural minerals and industrial solid wastes . The industrial solid wastes are relatively easily available and cheap with high reactivity, and usually appear where large quantities of CO 2 are emitted.…”

Accelerated carbonation by cement kiln dust in aqueous slurries: chemical and mineralogical investigation

“…However, despite the well documented advantages, the technology is not mature yet. 14,15 Some of these drawbacks could be avoided when alkaline wastes are used as feedstock instead of mineral resources. 10,12 The main reasons for limited application on a larger scale are the low reaction conversion, the slow kinetics and the energy intensity of the accelerated carbonation processes, which affect the economic viability of the technology.…”