Recycling Jorf Lasfar fly ash as an additive to cement

Labortory of solid state chemistry, Department of chemistry, Faculty of Sciences, B.P.1014, Rabat, Morocco.

^* Khadijanabih@ Yahoo.fr

Abstract

Recycling fly ash is a good example of valorization of waste. It gives a solution the environmental problem by avoiding land filling, and reducing CO2 emission in the atmosphere. In this work we studied the physical-chemical characteristics of Jorf Lasfar fly ash. The parameters investigated were particle size, density, specific surface Blaine, chemical and mineralogical compositions. The techniques used are scanning electronic microscope (SEM), transmission electronic microscope (TEM), X-rays fluorescence (XRF), X-rays diffraction (XRD) and atomic spectrometry emission coupled with inductive plasma ICP. We also conducted a study on the mechanical behavior of type CPJ45 cements produced from a combined grinding of clinker, limestone and gypsum. The substitution of a portion of the clinker by different percentages of fly ash was conducted. We noticed that the compression and bending resistances for these mixtures went through a maximum at 28 days with the addition of 7% (by mass) of ash. This result showed that the mineral and chemical compositions of this ash conferred a Pozzoulanic power to the cement studied.