# Alkaline Extraction of Organomineral Potassium Humate from Coal Mining Waste
## 3 Results and Discussion
### Kinetic Study of the Alkaline Extraction Process  
This section presents the results of studies to determine the regime parameters of the process of alkaline extraction of coal mining waste with potassium hydroxide. Crushed coal mining waste was used to conduct experimental studies. Taking into account the known data on humate extraction [16], the duration of the process was selected within 60-100 min, and the concentration of potassium hydroxide was 1%. The effectiveness of the investigated process was evaluated by the degree of extraction (\(\alpha\)). Experimental studies were carried out at various temperature conditions (60-100 \({}^{\circ}\)C). In the process of alkaline extraction by the recalculation of pH according to the formula [H+] = 10\({}^{-\mathrm{pH}}\), the concentration of pulp C, mol/L was observed. Using this value, the  
From the experimental work performed, it was determined that the degree of extraction (\(\alpha\)) rises with increasing time and temperature.The decrease in the yield of the product at high 100 \({}^{\circ}\)C and a time duration of 90-100 min is due to the fact that during the research there was intense evaporation of the pulp, although the degree of extraction at these values washigher. Experimental studies conducted at 80 \({}^{\circ}\)C and 90 min were determined as optimal regime parameters of potassium humate extraction. Kinetic processing of experimental data of potassium humate extraction process from coal mining waste was performed according to Formula (2), and is shown in Table 5.  
Based on the data in Table 5, a dependency plot of \(1-\frac{2}{3}\alpha-(1-\alpha)^{\frac{2}{3}}=f(\tau)\) was constructed (Figure 7). \begin{table}
\begin{tabular}{c c c c} \hline \hline
**Time, min** & **pH** & **C, mol/L** & **\(\alpha\), \%** & **Product Yield, gr** \\ \hline  & & 60 \({}^{\circ}\)C & \\ \hline
60 & 9.69 & 0.000000000204 & 37.11 & 40.76 \\
70 & 9.61 & 0.000000000245 & 49.73 & 45.51 \\
80 & 9.54 & 0.000000000288 & 56.08 & 49.18 \\
90 & 9.46 & 0.000000000346 & 61.12 & 53.75 \\
100 & 9.31 & 0.000000000489 & 64.76 & 56.57 \\ \hline  & & 80 \({}^{\circ}\)C & \\ \hline
60 & 8.57 & 0.000000002691 & 48.85 & 52.19 \\
70 & 8.49 & 0.00000003235 & 57.16 & 57.28 \\
80 & 8.33 & 0.00000000467 & 70.70 & 65.21 \\
90 & 8.25 & 0.00000005623 & 87.03 & 73.84 \\
100 & 8.11 & 0.000000007762 & 85.98 & 71.66 \\ \hline  & & 100 \({}^{\circ}\)C & \\ \hline
60 & 8.03 & 0.000000009332 & 62.96 & 62.71 \\
70 & 7.96 & 0.00000010964 & 66.84 & 68.16 \\
80 & 7.92 & 0.00000012022 & 78.09 & 66.94 \\
90 & 7.91 & 0.000000012302 & 89.01 & 65.36 \\
100 & 7.90 & 0.000000012589 & 88.12 & 62.23 \\ \hline \hline \end{tabular}
\end{table} 
Table 4: Results of experimental studies on the extraction of potassium humate. \begin{table}
\begin{tabular}{c c c} \hline \hline \(\alpha\) **(Unit Fraction)** & **1\(-\frac{2}{3}\alpha-(1-\alpha)^{\frac{2}{3}}\)** & **\(\tau\)** \\ \hline  & 60 \({}^{\circ}\)C & \\ \hline
0.3711 & 0.321241 & 60 \\
0.4973 & 0.303349 & 70 \\
0.5608 & 0.291102 & 80 \\
0.6112 & 0.279459 & 90 \\
0.6476 & 0.269809 & 100 \\ \hline  & 80 \({}^{\circ}\)C & \\ \hline
0.4885 & 0.304858 & 60 \\
0.5716 & 0.288761 & 70 \\
0.7070 & 0.251387 & 80 \\
0.8703 & 0.174138 & 90 \\
0.8598 & 0.180902 & 100 \\ \hline  & 100 \({}^{\circ}\)C & \\ \hline
0.6296 & 0.274721 & 60 \\
0.6684 & 0.263764 & 70 \\
0.7809 & 0.222527 & 80 \\
0.8901 & 0.160306 & 90 \\
0.8812 & 0.166712 & 100 \\ \hline \hline \end{tabular}
\end{table} 
Table 5: Results of experimental data processing. The reaction rate constants are found along the tangent of the angle of the straight line to the abscissa axis shown in Figure 7:  
* at 60 \({}^{\circ}\)C, \(\text{tg}_{\varphi 1}=\text{k}_{1}=0.0005458\);
* at 80 \({}^{\circ}\)C, \(\text{tg}_{\varphi 2}=\text{k}_{2}=0.0003379\);
* at 100 \({}^{\circ}\)C, \(\text{tg}_{\varphi 0.3}=\text{k}_{3}=0.0001375\). The \"apparent\" activation energy of the process of alkaline extraction of potassium humate was determined graphically.