In all three graphs, the pressure drop trend with time at different temperatures shows a similar pattern. At higher temperatures, the carbonation reaction seems to complete more quickly and achieve the ultimate pressure drop faster. The results show a significant difference in the ultimate pressure drops reached at the end of the carbonation at different temperatures. However, unlike the W/S ratio tests, in this case the pressure reduction does not provide a good indication to measure the amount of CO2 sequestered into the fly ash material, since the pressure is dependent on the temperature. Therefore, for a meaningful comparison, the pressure reduction data were converted to the Apatinib number of CO2 sequestered in each case, by applying ideal gas law. For this purpose, the behavior of CO2 gas was assumed to be similar to an ideal gas under test conditions (Montes-Hernandez et al., 2009). Equations (5) and (6) show the ideal gas law and its rearrangement to calculate the mole numbers.equation(5)PV=nRTPV=nRTequation(6)n=PV/RTn=PV/RTwhere P is the pressure drop due to carbonation and V is the rector volume occupied by CO2 gas. Since part of the reactor is occupied by fly ash and water, the remaining space should be considered as the gas-filled volume. To estimate this, the volume occupied by fly ash and water was deducted from the total inner volume of the reactor cell. T is the absolute temperature and R refers to the universal gas constant of 0.08314472 L bar/K mol. Fig. 9 compares the CO2 sequestration in three Latrobe Valley fly ashes under different reaction temperatures.