Evaluation of the Reactivity of Artificial Mixtures of Portland Cement Clinker Obtained by Flame Spray Pyrolysis ANDRÉS FELIPE PINTO, JORGE IVÁN TOBÓN, NATALIA BETANCUR-GRANADOS and OSCAR JAIME RESTREPO-BAENA* Cement and Construction Materials Group, Department of Materials and Minerals, National University of Colombia Medellín Campus, Medellín 050036, Colombia. Abstract The Portland cement clinker consists of 95% calcium oxide, silicon, aluminum and iron and 5% impurities of magnesium, sodium, potassium, titanium, sulfur, phosphorus and manganese. The constituents of the white clinker, formed from the combination of two or more of these main oxides, correspond to alite (3CaO.SiO 2 or C 3 S), belite (2CaO.SiO 2 or C 2 S) and celite (Ca 3 Al 2 O 6 or C 3 A), giving to cement its characteristic properties. The fundamental properties of cement are its mechanical resistance, chemical resistance, hydraulic behavior and heat release during hydration. In this work, the reactivity of an artificial mixture of white clinker, formed from alite, belite and celite prepared by flame spray pyrolysis was evaluated. The phases were characterized by X-ray diffraction, scanning electron microscopy and microcalorimetry, to evaluate their formation and reactivity. The characterization showed that during the synthesis of belite, a greater amount of the polymorph alpha was produced, with some impurities. On the other hand, the synthesis of celite allowed the production of the polymorph CII. The reactivity was evaluated by microcalorimetry. Material Science Research India www.materialsciencejournal.org ISSN: 0973-3469, Vol.16, No.(2) 2019, Pg.110-117 CONTACT Oscar Jaime Restrepo-Baena ojrestre@unal.edu.co Cement and Construction Materials Group, Department of Materials and Minerals, National University of Colombia Medellín Campus, Medellín 050036, Colombia. © 2019 The Author(s). Published by Oriental Scientific Publishing Company This is an Open Access article licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License Doi:http://dx.doi.org/10.13005/msri/160204 Article History Received: 30 March 2019 Accepted: 25 May 2019 Keywords Flame Spray Pyrolysis, Nanoparticles, Reactivity, Oxidant Flame, Clinker. Introduction Portland cement is a type of material obtained from the rotary kiln cooking of a mixture of limestone and clay in a rotary kiln, which is brought to sinter to form an intermediate product called clinker, which is mixed with gypsum, giving rise to Portland cement. 1 The clinker consists of 95% of calcium oxides, silicon, aluminum and iron and 5% of impurities of magnesium, sodium, potassium, titanium, sulfur, phosphorus and manganese. The main constituents of the white clinker are correspond to alite(3CaO.SiO 2 or C 3 S), belite (2CaO.SiO 2 or C 2 S)