Quantification of Transitions in Fly Ash-Zeolite and NaOH-Water Systems

3 Quantification of Transitions in Fly Ash-Zeolite and NaOH-Water Systems 

A correlation of transitions of pH (refer Fig. 6.19) and electrical conductivity, EC (refer Fig. 6.20) elucidates some interesting effects of the three-step activation process. These figures exhibit that a reduction in both pH and EC of the supernatant influences some critical residues (viz., 0.5-PT-12, 1.5-PT-12, 3.0-PT-12 and 2.0-PT-36) of Step-1, 0.5-R1-12, 0.5-R2-12 and 1.5-R1-12 of Step-2, 1.5-R2-12, 

Based on these variations in the ST and the residues, the X-ray diffraction patterns and FEG-SEM micrographs of the critical residues are presented in Figs. 6.22 and 6.23, respectively. 

It can be noticed from Fig. 6.22 that wide alteration in the mineralogy of the residues takes place and this results in the dissolution of peaks (viz., Quartz and Mullite, designated as Q and ML, respectively), which become boon for the formation of zeolitic minerals (viz., Na-Pl, Chabazite, Hydroxy-sodaUte and Faujasite designated by P, C, S and F, respectively). 

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