Correlation Between CEC and SAR

An attempt has been made to develop a correlation between the CEC and SAR of the residues, as depicted in Fig. 5.20. It is clear from this figure that the CEC decreases with an increase in SAR. However, the rate of this decrease (defined in terms of the slope of the relationship) is significantly steep for the AHA, as compared to the ALA. This also demonstrates that the OHA is a much more active and suitable material to synthesize a higher grade of cation exchanger (i.e., a zeolite) 

Based on the X-ray diflEractograms of both these ashes (OLA and OHA) and their activated residues, as depicted in Fig. 5.21a, b, results obtained after peak matching with the help of JCPDS data files [35] have been listed in Table 5.38. It can be deciphered from these results that the ALA samples contain fewer crystals of zeolite Na-Pl (refer Fig. 5.6). Most specifically, the residue ALA6 exhibits the presence of the zeolite Na-Pl for M and Hydroxy-sodalite for M [23]. On the other hand. Fig. 5.4b exhibits the peaks corresponding to the zeolites Na-Pl and Hydroxy-sodalite in the residue, AHA2. However, as listed in Tables 5.4 and 5.5, the zeolites, Cancrinite and Analcime, were also found in the residue AHA6. This 

From Fig. 5.22a, b it can be seen that both OHA and OLA samples are enriched with spheroidal and oval particles, which may correspond to glass and Quartz, respectively [10]. However, Fig. 5.22a exhibits some whitish spherules (zeolite 

Note ZD suffixed by 1, 2, 3 and 4 represent zeolite doses e.g. 0.6, 1.0, 1.66 and 5.0 gA, respectively. A number after hyphen indicates the interaction time in hours 

Na-Pl with large surface pores) deposited on the OLA samples, due to the ash-water interaction taking place in the lagoon [46, 48, 49]. In contrast, the micrograph of the OHA (as depicted in Fig. 5.22b), reveals many smooth and spherical (Quartz, Mullite) to irregular particles (carbon, Hematite and/or Magnetite) as reported by Adamczyk and Bialecka [32] and Nugteren et al. [17]. 

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