White Metakaolin: Factors Influencing on Coloring and Evaluating Methods

Results of color characteristics of the white metakaolin of ZAO «Plast Rifey» measured according to recommendations of the International Commission on Illumination (Commission Internationale de l’Éclairage, CIE) are presented. White metakaolin has high values of chromaticity and lightness corresponding to yellowish-red tone simultaneously. The lightness of metakalin is determined by the content of kaolinite in the kaolin composition, dispersion of particles, and temperature of thermal treatment. It is shown that the content of iron oxides is a significant factor which determines the value of whiteness index WISO, but it is not dominating. It is established that the higher pozzolanic activity of metakaolin within the temperature range of 600–950оC, the higher values of redness а* CIEL*a*b*. The gradation of metakaolin according to the whiteness index and color characteristics CIEL*a*b*.is presented, the data are recommended to include in the normative document.

R.A. PLATOVA¹, Candidate of Sciences (Engineering)(This email address is being protected from spambots. You need JavaScript enabled to view it.)
Yu.T. PLATOV¹, Doctor of Sciences (Engineering)
T.M. ARGYNBAEV², General Director
Z.V. STAFEEVA², Deputy Director for production

¹ Plekhanov Russian University of Economics (36, Stremyanny Passage, 117997, Moscow, Russian Federation)36, per. 36, Moscow, 117997, Russia
² OOO «Plast Rifey» (1, Magnitogorsky Tract, Plast, 457020, Chelyabinskay Oblast, Russian Federation)

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