Efficiency of fly ash belite cement and zeolite matrices for immobilizing cesium.

Modifications of the C - S - H gel by hydration at 40 o C of belite cements from coal fly ash Class

SEM/EDX characterization of the hydration products of belite cements from class C coal fly ash

This paper presents the microscopic characterization of two types of fly ash belite cements and their hydration products by means of scanning electron microscopy (SEM), energy-dispersive X-ray (EDX) microanalysis and X-ray diffraction analysis. The cements were obtained from ASTM class C coal fly ash by the hydrothermal-calcination route in water (FABC-2-W) and NaOH 1M solution (FABC-2-N). The ...

Resistance of class C fly ash belite cement to simulated sodium sulphate radioactive liquid waste attack.

The resistance of class C fly ash belite cement (FABC-2-W) to concentrated sodium sulphate salts associated with low level wastes (LLW) and medium level wastes (MLW) is discussed. This study was carried out according to the Koch and Steinegger methodology by testing the flexural strength of mortars immersed in simulated radioactive liquid waste rich in sulphate (48,000 ppm) and demineralised wa...

Effect of nanosilica additions on Belite cement pastes held in sulfate solutions

Fly Ash Belite cement (FABC) pastes with and without nanosilica additions have been prepared and maintained in sulfate solutions (Na2SO4 0.5 M) for 180 days. The mechanical performance and the changes in microstructure have been monitored at 28, 90 and 180 days by compressive strength, X-ray diffraction (XRD) and Si MAS NMR measurements. We have found that, unexpectedly, and contrary to what ha...

Competitive Adsorption of Cu, Ni, Pb, and Cd from Aqueous Solution Onto Fly Ash-Based Linde F(K) Zeolite

The reaction of fly ash with a KOH solution was used to synthesize Linde F(K) zeolite, following which Fourier transform infrared spectroscopy were used to characterize the crystalline material. The competitive adsorption of Cu, Ni, Pb, and Cd onto this zeolite was subsequently studied in quaternary solution systems. The results show that the metal removal rates gradually increase with incr...