Papers by Author: Alexander Pisch

Abstract: This paper focuses on the carbonation of non-hydraulic binders based primarily on wollastonite (CaSiO₃) in order to study the relationship between clinker composition, curing conditions and compaction on carbonation reaction rate. Decoupled carbonation and drying experiments are carried out using cements at different CaO/SiO₂ ratio, at 60 °C, 1 bar of CO₂ and multiple RH (relative humidity) and compaction degrees. Solid analysis include mass gain or loss, TGA, XRF and Carbon/Hydrogen (CH) to determine respectively the bound H₂O content, CO₂ content and the mineralogical assemblage. Relative humidity strongly influences carbonation intrinsic reaction rate, while compaction seems to be a second order mechanism. Testing procedure can be used to discriminate the reactivity of clinkers with various initial phase assemblage.

Abstract: Sintering of nickel ferrite is strongly enhanced by carbonaceous debinding. It is shown that this effect can be easily explained through thermodynamic consideration on oxygen potential and content evolution during the sintering operation. DTG and dilatometry experiment are in good agreement with driving force calculation and phase diagrams analysis.