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It has been found that the addition of certain components, despite their low concentration in raw mix, may accelerate and enhance the reactivity of the cement raw mix. The utilization of mineralizers to facilitate and quicken the process of clinkerization backpedals numerous years, the concept of using such mineralizers to burn normal raw mixes at a much lower temperature with the end goal of decreasing the fuel necessities of the furnace and to enhance the cement proprieties has become to be seriously considered over the most recent couple of years. The subject of this paper is to investigate the impact of calcium fluoride as mineralizer on addition during the clinkerization process of industrial raw mixtures and its effect on chemical, mineralogical, and mechanical properties of CPA Moroccan cement. Five different raw meals were utilized and were burned with 2% of calcium fluoride. The resulting clinker was analyzed by X-ray diffraction (XRD) and fluorescence spectroscopy to determine the chemical phases of the obtained clinker, and the mechanical properties of resulting CPA cement were determined. The results show that the addition of 2% of CaF 2 to the clinker raw meal induced a decrease in the burning temperature and free lime, while improving the clinker phase formation and the mechanical properties of obtained cement.

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The aim of this study is the synthesis and investigation of bioactive response of acrystalline silicophosphate.A monophasic silicocarnotite was elaborated by solid state reaction from a mixture of beta-tricaliciumphosphate and dicalcium silicate based on mussel shells according to the diagram of system Ca3(PO4)2–Ca2SiO4, at 65 % and 35% respectively , these starting materials are heated up to 1450 °C to obtain a monophasic silicocaronitite. The obtained result probed that the main crystalline phase which was detected and recognized in the heated sample at 1400 and 1450 °C was a well-crystallized silicocarnotite. The test of bioactivity of silicocarnotite in artificial saliva causes the appearance of a reaction layer on the materials surface after 4 hours soaking and growth up during 30 days.This layer is constituted of a biphasic mixture of Si–Ca–P–H material, silicated hydroxyapatite and hydroxyapatite phase are the mainly developing ones with increasing soaking time.The analysis and characterization of the precipitated appearing on the material surface has confirmed experimentally the in vitro bioactivity of silicocarnotite monophasic material.

In recent years, waste recycling has become a key issue in construction materials science for achieve the goal of sources of raw materials. The aim of this study is to use waste glass as source of SiO2 oxide and mussel shells consisting essentially of calcium carbonate as starting materials to synthesize belite rich cement. The elaborated clinker is chemically and structurally related to β-Ca2SiO4, by heat solid state activation. After grinding, the raw materials are mixed and heated up to 1050°C. The samples are characterized by X-ray diffraction (XRD) and Fourier Transformed Infrared spectroscopy (FT-IR). The mechanical strength of some sample was measured for 28 and 72 days. The results show the different mineralogical stapes of formation of clinker, the state reaction method allows the elaboration of a cementitious material by a simple heat treatment at relatively low temperature and low release of CO2. The hydration products are also identified by XR diffraction at 2, 7, 28 and 72 days.