Study on high-efficiency CO2 absorption by fresh cement paste

Influences of CO2‐cured cement powders on hydration of cement paste

“…In the light of the foregoing statement, the ability to sequestrate CO 2 by hydrated cement paste could be confirmed, which is in line with the existing literature 50,55 . According to the results, different CO 2 pressures could result in the various extents of carbonation, which led to the formation of various types of CCP differing in the carbonation product content 56 . Nevertheless, the hydration products of CCP‐OPC paste with different replacement levels were the same, 26 but there is a discrepancy between the theoretical and real CO 2 capture by CCP.…”

“…50,55 According to the results, different CO 2 pressures could result in the various extents of carbonation, which led to the formation of various types of CCP differing in the carbonation product content. 56 Nevertheless, the hydration products of CCP-OPC paste with different replacement levels were the same, 26 but there is a discrepancy between the theoretical and real CO 2 capture by CCP. Meanwhile, the hydration behaviors of CCP-OPC paste were further explained as follows.…”

“…Similarly, the decrease of the slump-flow in CCP-OPC pastes was related to the water consumption during the CO 2 curing. 56 Owing to the carbonation reaction between the CO 2 and CH, the absorption of CO 2 altered the inner structure of the hydrated cement paste. Hence, the free water in the hydrated cement pastes was gradually consumed as a result of the carbonation reaction.…”

Application of Fourier Transform infrared spectroscopy (FTIR) coupled with multivariate regression for calcium carbonate (CaCO3) quantification in cement

“…Greenhouse gases (GHG) influence on the environment is one of the humanity's greatest concerns in the 21st century. Emissions of greenhouse gases, such as methane (CH 4 ) and carbon dioxide (CO 2 ), are among the main drivers of global warming [1][2][3]. Currently, the main sources of GHG emissions are related to: (i) energy from fossil fuels, (ii) land use change and deforestation and (iii) decomposition of minerals (carbonates) [1,[4][5].…”

“…The main components of cementitious materials are sensitive to the CO 2 action and are subject to the carbonation process [3,29]. These chemical processes produce calcium carbonate (CaCO 3 ) and amorphous silica, among other minority compounds, which induce several changes in the chemical composition, mechanical strength, and pore size distribution of the cement matrix [30].…”