## 4 Efficacy Studies for Water
### Petrol Remediation  
It was observed that with a sorbent dose of 0.5 g at room temperature (25 \({}^{\circ}\)C) and at a pH value of 7, the petrol uptake efficiencies of nano-silica and nano-zeolite were measured at 95% and 85%, respectively [20]. The sorption rate for this investigation was calculated using the kinetic and isotherm models. The results showed that sorption is highly successful, and the percentage of pollutants eliminated is proportional to the amount of sorbent used. Second-order adsorption kinetics provided a more precise explanation of gasoline sorption; moreover, the Langmuir isotherms provided the most accurate description of sorption. The kinetic results also revealed that nano-silica and nano-zeolite (NZ) absorbed more gasoline; nevertheless, both sorbents reached saturation after 40 min of contact time. The study represents an important aspect since it represents the removal of aquatic pollutants  
\begin{table}
\begin{tabular}{c c c c c} \hline \hline \multirow{2}{*}{**Compounds**} & **Barley-Grass-** & **Wheatgrass-** & **Barley-Husk-** & **Rice-Husk-Synthesized** \\  & **Synthesized** & **Synthesized** & **Synthesized** & **Nano-Amorphous** \\  & **Nano-Amorphous** & **Nano-Amorphous** & **Silica\%** & **Silica\%** \\ \hline SiO\({}_{2}\) & 96.203 & 93.01 & 96.30 & 96.51 \\ K\({}_{2}\)O & 1.510 & 0.297 & 1.410 & 0.297 \\ SO\({}_{3}\) & 0.855 & 0.168 & 0.855 & 0.168 \\ CaO & 0.797 & 0.157 & 0.697 & 0.157 \\ Fe\({}_{2}\)O\({}_{3}\) & 0.422 & 0.083 & 0.322 & 0.17 \\ Cr\({}_{2}\)O\({}_{3}\) & 0.067 & 0.013 & 0.067 & 0.013 \\ MnO & 0.058 & 0.011 & 0.058 & 0.011 \\ CuO & 0.048 & 0.009 & 0.048 & 0.009 \\ ZnO & 0.020 & 0.004 & 0.220 & 0.004 \\ \hline \hline \end{tabular}
\end{table}
Table 2: XRF compositions of nanoparticles from different sources.  
using nano-sorbents fabricated using agricultural waste, hence, enhancing environmental sustainability. These nanoparticles have a high affinity for gasoline impurities and might be used to remove oily/greasy contaminants in almost all types of aquatic settings, which could have been caused by accidental oil spills, sea harbor contamination, and other similar occurrences. Thus, by utilizing nano-silica and nano-zeolite for the removal of gasoline from polluted water, this study proposes a novel method with a better durability effect for the remediation of pollution originating from spills of gasoline and other petroleum products.  
Application of Magnetic Nano-Silica on Diesel Oil  
In another study [30], we studied the influence of contact time, and it was shown that the absorption of petrol pollutants began at 2 min at a rate of 20%, while increased sorption efficiency began at 5 min. The pollutant absorption rose to 65% after 8 min and 80% at 10 min. At 12 min, the greatest absorption rate of 85% was obtained, and the rate remained stable until the trial ended at approximately 22 min. This demonstrates that the sorption of petrol pollutants using magnetic nano-silica takes about 12 min to reach equilibrium. The sorption experiment progressed in time, indicating that sorption increased as time passed until the equilibrium time was attained. Low percentages of petroleum impurities were absorbed by nano-silica at low pH values of between 4 and 6, and due to the dependency of the pH value of the solution, the efficacy of petroleum mitigation was studied and documented. At pH 6, the absorption of pollutants began to increase, and by pH 7, the uptake had reached its peak. However, as the pH was raised further, the uptake efficiency began to decrease, with a substantial reduction in uptake observed between pH 8 and 10; hence the ideal pH for the adsorption of petroleum pollutants by MNSPs is -pH 7, according to this study.