## 3 Results and Discussion
### Characterization of the Zeolite Sediments  
Chemical analysis of NZ and its modified variants showed distinctive variations among chemical properties (Table 3). NaOH-modified NZ showed the highest pH (9.76-11.23), which was quite anticipated due to the alkali treatment of NZ. On average, pH values were increased by 3.10 and 2.11 units, respectively, for micro and nano variants of NaOH-treated sediments. pH was decreased by 3.01 and 3.62 units in HCl-M and HCl-N sediments against NZ sediments, suggesting a possible impact of acidic treatment of NZ, whereas minor variations were found among pH of NZ (NZ-M, NZ-N), LDH (LDH-M), and NaCl (NaCl-M, NaCl-N) sediments, and pH was increased by the following trend: NaCl > LDH > NZ. In general, a decline in pH value was noted by converting sediments from microparticle size to nanoparticle size, suggesting protonation of surface functional groups by pretreatment of NZ sediments [22]. The EC of all examined sediments was found to be consistently low, and the highest EC was found in NaOH-M (2.30 dS m\({}^{-1}\)), followed by NaCl-M (1.99 dS m\({}^{-1}\)) and NZ-M (1.89 dS m\({}^{-1}\)). Similar to pH, a decline in EC value was recorded by converting sediment particle size from micro- to nanoparticles. All sediments showed a high CEC value, indicating the presence of exchangeable cations and oxygenated surface functional groups. Again, nanoparticle size variants of sediments showed plausible increases in CEC, and the highest CEC was found in LDH-N (81.74 cmol kg\({}^{-1}\)), followed by LDH-M (72.22 cmol kg\({}^{-1}\)), NaOH-N (68.87 cmol kg\({}^{-1}\)), and NZ-N (62.43 cmol kg\({}^{-1}\)). Similar results were reported by [PERSON] et al. [41] and [PERSON] and [PERSON] [42], who found an increment in CEC of LDH and NaOH-treated NZ sediments. Also, the occurrence of oxygenated surface functional groups in LDH and NaOH-treated NZ was confirmed by FTIR, which could be a possible reason for the high CEC value of these sediments. \begin{table}
\begin{tabular}{c c c c c c} \hline
**EC** & **pH** & **CEC** & **OM** & **CaCO3** & **Texture** \\
**(dSm\({}^{-1}\))** & **(12.5)** & **(cmol kg\({}^{-1}\))** & **(\%)** & **(\%)** & **(\%)** \\ \hline
0.4 \(\pm\) 0.1 & 7.8 \(\pm\) 0.2 & 9.3 \(\pm\) 1.2 & 0.8 \(\pm\) 0.1 & 2.4 \(\pm\) 0.4 & Sandy loam \\ \hline \multicolumn{6}{c}{**Total Metal Concentration (mg/kg)**} \\ \hline
**Cd** & **Cu** & **Ni** & **Pb** & **Zn** & **As** \\ \hline
13.0 \(\pm\) 1.6 & 458.1 \(\pm\) 8.6 & 116.7 \(\pm\) 0.4 & 193.5 \(\pm\) 0.3 & 1864.1 \(\pm\) 0.9 & 16.2 \(\pm\) 0.8 \\ \hline \multicolumn{6}{c}{EC, electrical conductivity; CEC, cation exchange capacity; OM, organic matter; CaCO, calcium carbonate. Values are presented as averages followed by \(\pm\)1 SD.} \\ \end{tabular}
\end{table} 
Table 2: Physiochemical characteristics and total contents of trace elements in the collected soil. \begin{table}
\begin{tabular}{c c c c} \hline
**No** & **Sediments** & **pH (1:5 _w/v_)** & **EC (dSm\({}^{-1}\))** & **CEC (cmol kg\({}^{-1}\))** \\ \hline
1 & NZ-M & 8.1 \(\pm\) 0.1 & 1.9 \(\pm\) 0.1 & 17.1 \(\pm\) 1.1 \\
2 & NZ-N & 7.6 \(\pm\) 0.1 & 0.3 \(\pm\) 0.1 & 62.4 \(\pm\) 1.4 \\
3 & LDH-M & 8.3 \(\pm\) 0.1 & 0.7 \(\pm\) 0.1 & 72.2 \(\pm\) 1.5 \\
4 & LDH-N & 7.9 \(\pm\) 0.1 & 0.6 \(\pm\) 0.1 & 81.7 \(\pm\) 1.9 \\
5 & HCl-M & 6.1 \(\pm\) 0.1 & 0.3 \(\pm\) 0.1 & 35.2 \(\pm\) 1.0 \\
6 & HCl-N & 6.0 \(\pm\) 0.1 & 0.2 \(\pm\) 0.1 & 60.3 \(\pm\) 1.4 \\
7 & NaOH-M & 11.2 \(\pm\) 0.2 & 2.3 \(\pm\) 0.1 & 36.1 \(\pm\) 1.1 \\
8 & NaOH-N & 9.7 \(\pm\) 0.2 & 1.3 \(\pm\) 0.1 & 68.8 \(\pm\) 1.8 \\
9 & NaCl-M & 8.9 \(\pm\) 0.1 & 1.9 \(\pm\) 0.1 & 24.8 \(\pm\) 1.1 \\
10 & NaCl-N & 8.0 \(\pm\) 0.1 & 0.8 \(\pm\) 0.1 & 49.7 \(\pm\) 1.3 \\ \hline \end{tabular}
\end{table} 
Table 3: Chemical characteristics of collected and modified NZ sediments. The XRD analysis of raw and modified zeolite sediments indicated the presence of the mineral clinoptiolite (CP) (Figure 1).