Carbonation of natural pure and impure wollastonite

Autor: Christof Lempp, Herbert Pöllmann, Kristoff Svensson, Flora Feitosa Menezes, Andreas Neumann
Rok vydání: 2019
Předmět:
Zdroj: SN Applied Sciences. 1
ISSN: 2523-3971
2523-3963
DOI: 10.1007/s42452-019-0328-4
Popis: Wollastonite can be used as cementitious material, for example in carbon capture and storage (CCS application). The interaction of wollastonite (CS) and pure CO2 in the presence of H2O at temperature (333 K) relevant to injection conditions for CCS were investigated within the joint BMWi research project CLUSTER. The reaction which describes the formation of wollastonite during metamorphism, is reversed. Wollastonite reacts in the presence of CO2-pressure under aqueous conditions to form calcium carbonate and amorphous silicon oxide. To determine the driving force for this reaction it is important to investigate the impact of CO2 pressure (p) and temperature (T). The reaction kinetics of the carbonation reaction of wollastonite is strongly dependent to temperature. At 333 K and 2 MPa CO2 the $${\bar{\text{C}}}$$ CS reaction is fast (≤ 24 h). The chemical composition of wollastonite was analyzed by X-ray fluorescence. To determine the conversion rate of the reaction quantitatively powder X-ray diffraction with Rietveld method were applied. For further application, it is important to understand the specific reactions during the carbonation. Therefore, the influence of different treatments on wollastonite raw material (hydrochloric acid, acetic acid and temperature), before the carbonation experiments, on the carbonation reaction were investigated. The conversion of wollastonite, depending on temperature, was performed successfully. It could be proven, that aragonite acted as seed crystal for further aragonite formation. Furthermore, indications for the formation of aragonite out of amorphous CaCO3 were observed.
Databáze: OpenAIRE