High Environment Quahty method

The X-ray absorption spectroscopy (XAS) methods provide information about the electronic and structural properties of matter. Thus, X-ray absorption nearedge spectroscopy (XANES) is adequate for the observation of local electronic and geometric structures of elements, while extended X-ray absorption fine structure (EXAFS) provides information concerning the coordination environment of metals, metal ions, and nonmetals. To improve time resolution and spectral quahty, sophisticated techniques such as EDXAFS (energy-dispersive X-ray absorption fine structure spectroscopy) and HERFD XAS (high-energy resolution fluorescence detection X-ray absorption spectroscopy) have been developed. All mentioned X-ray methods have a common requirement for high-briUiance X-ray sources such as available at a synchrotron. 

In order to augment the quantity and quality of final synthesis yield as obtained from conventional hydrothermal activation, another modified method has been introduced which utihzes two different steps, an initial high temperature fusion of fly ash-alkah mixture, prior to employing the final stage of hydrothermal activation of the fused product. The main variables have been fusion temperature and time, alkali type and its concentration and crystallization time in hydrothermal synthesis process, which can affect the quahty and yield of final product. As such, it has been confirmed that the final yield can be quantified to exhibit zeolitic conversion up to 62 % together with by production of alkaline waste solution which can become a threat to the environment after disposal. A flowchart of the synthesis process is depicted in Fig. 3.3 [1, 2, 9, 10, 12, 43, 44]. 

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