# Separation of Conospheres from Lignite Fly Ash Using Acetone-Water Mixture
## 3 Results and Discussion
### Particle Size and Distribution
\begin{table}
\begin{tabular}{c c c c c c c c} \hline \hline \multicolumn{2}{c}{**Fly**} & \multicolumn{4}{c}{**Acetone/Water**} & \multirow{2}{*}{_D [4,3]_ (\(\upmu\)m)} & \multicolumn{4}{c}{**Weight Percentage Size Distribution (\%)**} \\ \cline{4-9}
**Ash/Medium** & & & & \(<\)**50 \(\upmu\)m** & **50–100 \(\upmu\)m** & **100–150** & **150–200** & \(>\)**200 \(\upmu\)m** \\ \hline \multirow{4}{*}{1:2.5} & 100:0 & 125.09 \(\pm\) 2.71 & 18.46 & 24.16 & 23.69 & 16.23 & 17.46 \\  & 80:20 & 131.42 \(\pm\) 2.79 & 18.50 & 21.19 & 23.49 & 16.63 & 20.18 \\  & 50:50 & 51.65 \(\pm\) 0.67 & 63.09 & 23.02 & 7.66 & 3.24 & 2.99 \\  & 20:80 & 38.17 \(\pm\) 1.21 & 68.98 & 25.74 & 4.98 & 0.30 & n/a \\ \hline \multirow{4}{*}{1: 5} & 100:0 & 91.56 \(\pm\) 2.99 & 31.85 & 31.22 & 19.17 & 9.98 & 7.79 \\  & 80:20 & 141.21 \(\pm\) 3.01 & 11.48 & 22.89 & 25.66 & 18.2 & 21.77 \\  & 50:50 & 113.55 \(\pm\) 1.10 & 18.43 & 30.33 & 24.77 & 13.81 & 12.66 \\  & 20:80 & 96.07 \(\pm\) 1.33 & 29.80 & 30.96 & 19.62 & 10.01 & 9.61 \\ \hline \multirow{4}{*}{1:10} & 100:0 & 147.76 \(\pm\) 2.33 & 13.60 & 19.58 & 23.40 & 17.84 & 25.58 \\  & 80:20 & 110.57 \(\pm\) 4.75 & 29.67 & 24.07 & 18.18 & 12.50 & 15.58 \\ \cline{1-1}  & 50:50 & 60.67 \(\pm\) 2.64 & 60.35 & 19.15 & 9.35 & 5.03 & 6.12 \\ \cline{1-1}  & 20:80 & 82.85 \(\pm\) 1.86 & 41.18 & 27.56 & 15.24 & 8.11 & 7.90 \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Analysis of particle size and weight percentage size distribution of cenospheres collected from using different ratios of freshly prepared acetone–water mixtures, a 4-h soaking period, and fly ash/medium ratios of 1:2.5, 1:5, and 1:10. _D [4,3]_: diameter. Figure 2: Mean diameters of cenospheres collected from using different ratios of freshly prepared acetone–water mixtures, a 4-h soaking period, and fly ash/medium ratios of 1:2.5, 1:5, and 1:10. The particle size distribution profiles of the collected cenosphere fractions are demonstrated in Figure 3 as a function of the fly ash content in the medium. Figure 3a,b reveals the asymmetric particle size distribution, and Figure 3c reveals the nearly normal Gaussian particle size distribution. The profile close to the normal Gaussian particle size distribution is regarded as the best one, considering that the population lies below \(D_{10}\), \(D_{50}\), and \(D_{90}\)[23]. For certain applications, the uniformity of particle size and weight distributions of cenospheres is preferred for the use of cenospheres as fillers and additives, which affects the mechanical properties of the final products [32; 39]. At a 1:2.5 ratio, high fly ash concentration appeared to have a strong effect on the selective size distribution as a function of the medium fraction relating to density. The clear discrete groups of distribution for the large-sized fractions (100:0 and 80:20 ratios) and the smaller-sized fractions (50:0 and 20:80 ratios) are seen in Figure 3a. For the more diluted fly ash/medium ratio of 1:10, all fractions of the collected cenospheres appeared to have a similar profile of particle size distribution in the large-sized range. The dilution parameter in terms of low fly ash content in the medium facilitated the large-sized particles in the low liquid density to easily escape from the ash agglomeration and float to the surface with respect to the small-sized particles. Figure 3: Particle size distribution profiles of cenospheres collected from using different ratios of freshly prepared acetone–water mixtures, a 4-h soaking period, and fly ash/medium ratios of (**a**) 1:2.5, (**b**) 1:5, and (**c**) 1:10.