## 4 Results and Discussion
### Acid Neutralization  
Neutralization of typical acids using nanoactive oxide neutralizers is a very costly process. Such neutralizers currently available on the market cost over 50 euro/kg. For the sake of comparison, the cost of commercially available technical grade NaHCO\({}_{3}\) can be less than 1 euro/kg and the CaO available in any building store comes up to only 0.2 euro/kg. The neutralization process using FA showed a neutralization efficiency of 0.95 kg calculated as pure H\({}_{2}\)SO\({}_{4}\) per 1 kg of MgO-TiO\({}_{2}\). It is easy to calculate that, for example, the use of CaO would allow the neutralization of 1.75 kg H\({}_{2}\)SO\({}_{4}\) (and with a product fully neutralized to CaSO\({}_{4}\)). Another solution that would be much cheaper than nanoactive oxide neutralizers would be the use of NaHCO\({}_{3}\), Na\({}_{2}\)CO\({}_{3}\), NaOH or even decahydrate of Na\({}_{2}\)B\({}_{4}\)O\({}_{7}\). Experiments show that without mixing and with big excess of H\({}_{2}\)SO\({}_{4}\) (mass ratio neutralizer: H\({}_{2}\)SO\({}_{4}\) 1:10), the energy effect of the neutralization process with nanocrystalline MgO-TiO\({}_{2}\) provides a slightly better guarantee of safety at the time of its adding than the solutions used so far (Figure 9, Table 3). While the temperature increase (at a weight ratio of neutralizer: H\({}_{2}\)SO\({}_{4}\) (1:10) for solid Ca(OH)\({}_{2}\) and NaOH was significantly greater causing boiling and spreading of the pool (\(\Delta\)T\({}_{\text{Ca(OH)2}}\) = 90.2 \({}^{\circ}\)C, \(\Delta\)T\({}_{\text{NaOH}}\) solid = 117.6 \({}^{\circ}\)C), small differences were observed for NaHCO\({}_{3}\) neutralization (\(\Delta\)T\({}_{\text{NaHCO3}}\) = 26.6 \({}^{\circ}\)C) as compared to FA (\(\Delta\)T\({}_{\text{MgO-TiO2}}\) = 19.3 \({}^{\circ}\)C). In the conditions of rescue and firefighting operations, the rate of the sodium bicarbonate neutralization process is sufficiently fast and does not require acceleration by mixing. On the other hand, nanocrystalline MgO-TiO\({}_{2}\) floats on the surface of the pool and reacts slowly, so mixing is necessary to speed up the reaction. The mixing process causes a two-fold increase in temperature (\(\Delta\)TMgO-TiO\({}_{2}\) = 46.0 \({}^{\circ}\)C) as compared to the reaction with free \begin{table}
\begin{tabular}{c c c} \hline \hline
**Neutralizer** & \(\Delta\)**T**\({}_{\text{c}}\)\({}^{\circ}\)**C** & **(\(\Delta\)T\(\Delta\)t\({}^{-1}\))\({}^{\circ}\)C s\({}^{-1}\)** \\ \hline MgO-TiO\({}_{2}\) (FA) & 19.3 & 0.8 \\ \hline NaHCO\({}_{3}\) & 26.6 & 1.9 \\ \hline Na\({}_{2}\)CO\({}_{3}\) & 35.6 & 2.1 \\ \hline Ca(OH)\({}_{2}\) & 90.2 & 7.9 \\ \hline NaOH & 117.6 & 10.7 \\ \hline CaO & 49.9 & 2.5 \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Temperature increase and maximum temperature change over time for neutralization processes 98% H\({}_{2}\)SO\({}_{4}\) through FA, NaHCO\({}_{3}\), Na\({}_{2}\)CO\({}_{3}\), Ca (OH)\({}_{2}\), NaOH, CaO. Mass ratio neutralizer: H\({}_{2}\)SO\({}_{4}\) 1:10. Method of adding the neutralizer: loose pouring (without mixing). T\({}_{0}\) = 20 \({}^{\circ}\)C.  
Figure 9: Temperature dependence as function of time in the process of neutralization 98% H\({}_{2}\)SO\({}_{4}\) through (**1**) FA (MgO-TiO\({}_{2}\)), (**2**) NaHCO\({}_{3}\), (**3**) Na\({}_{2}\)CO\({}_{3}\), (**4**) CaO, (**5**) Ca (OH)\({}_{2}\), (**6**) NaOH. Mass ratio neutralizer: H\({}_{2}\)SO\({}_{4}\) 1:10. Method of adding the neutralizer: loose pouring (without mixing). T\({}_{0}\) = 20 \({}^{\circ}\)C.  
pouring without mixing. Studies have shown that in the case of neutralization including mixing in the mass ratio of MgO-TiO\({}_{2}\) to H\({}_{2}\)SO\({}_{4}\) of 1:2, the temperature increase \(\Delta\)T can be as high as 170 \({}^{\circ}\)C, and consequently poses a more intense risk of burns due to careless operation of the rescuer than it is the case for NaHCO\({}_{3}\) at the same ratio (\(\Delta\)T\({}_{\rm NaHCOO3}\) = 74.8 \({}^{\circ}\)C).