Natural and accelerated mineral carbonation by petroleun coke fly ashes: Potential evaluation of their physical pretreatment

Abstract

Humanity is in a fight against time regarding the increase of CO2 emissions and its consequences. One of the technologies to reduce emissions is through mineral carbonation. Mineral carbonation by natural conditions is a slow process. Therefore, the operational variables are modified to increase the capture and also the speed of the process. Alkaline materials such as fly ash have been successfully used for this process. In this work, it is proposed fly ashes from petroleum coke combustion for the natural and accelerated capture of CO2 with and without physical pre-treatments such as stirring, grinding and sieving. Natural carbonation proved to be slow, while accelerated carbonation proved an effective, process, capturing up to 20.6%. By incorporating the stirring and sieving as physical pre-treatments, the CO2 capture is increased up to 18%, showing that the fly ash could be a potential material for mineral carbonation in aqueous medium.