# Adsorption of Coxsackievirus in Sediments: Influencing Factors, Kinetics, and Isotherm Modeling
## 4 Conclusions  
This study utilized the standard batch equilibrium method to explore the impact of various environmental factors in sediments, including different initial virus concentrations, particle sediment sizes, temperatures, pH values, and humic acid on the adsorption of CA16. Results showed that smaller sediment particle sizes, especially clay, exhibited heightened adsorption capacity for CA16 compared to silt, fine sand, medium sand, and coarse sand. Additionally, higher temperatures led to increased CA16 adsorption by sediment particles, resulting in a viral titer reduction from 2.17 log to 2.5 log as the temperature rose from 10 \({}^{\circ}\)C to 25 \({}^{\circ}\)C. The pH of the water significantly influenced sediment adsorption, with acidic environments showing higher efficiency than alkaline ones. Clay's adsorption capacity for CA16 decreased with rising pH (5.5 to 9.5), causing a 24.7% reduction in concentration decay. Moreover, the presence and concentration of humic acid were found to negatively impact the adsorption capacity of clay for CA16. The experimental data were fitted using adsorption kinetic models, with the pseudo-second-order model closely aligning with simulated results, exhibiting adjusted \(R^{2}\) values above 0.9. Conclusions drawn from static adsorption experiments indicate that higher initial CA16 concentrations resulted in lower relative adsorption capacities of clay, eventually reaching a maximum per unit of sediment. Furthermore, adsorption isotherm models revealed the Langmuir model as the most representative, outperforming the Freundlich model. These findings are vital for accurately assessing health risks associated with viral contamination in aquifers, offering crucial safety evidence. In the future, more geochemical factors will be considered to study the impact of the groundwater environment on the behavior of viruses with dynamic transport experiments.  
M.L.: Conceptualization, Investigation, Methodology, Formal analysis, Writing--original draft. X.Z.: Conceptualization, Methodology, Writing--review and editing, Funding acquisition. W.S.: Supervision, Writing--review & editing. F.C.: Supervision, Writing--review &  
Figure 8: Model fittings of CA16 adsorption data for the group with different initial concentrations (experiment 15–19); (**a**) [PERSON] isotherm model; (**b**) Langmuir isotherm model.  
\begin{table}
\begin{tabular}{c c c c} \hline \hline
**adsorption Isotherms** & **Model Equation** & **Adjusted \(R^{2}\)** & \(p\) Value** \\ \hline [PERSON] & \(Q_{e}=K_{e}C_{e}^{\frac{1}{2}}\) & 0.8748 & \textless{0.05} \({}^{\star}\) \\ [PERSON] & \(Q_{e}=\frac{Q_{e}K_{e}C_{e}}{T+K_{e}C_{e}}\) & 0.9826 & \textless{0.05} \({}^{\star}\) \\ \hline \hline \end{tabular} \({}^{\star}\)Calculating using Analysis of Variance (ANOVA) method.  
\end{table}
Table 3: Fitting parameters of [PERSON] and [PERSON] isotherm equations.  
editing. T.L.: Writing--review and editing. Z.D.: Methodology, Writing--review and editing. All authors have read and agreed to the published version of the manuscript.  
This work was supported by the National Natural Science Foundation of China (42272285).  
Not applicable.  
The data presented in this study are available on request from the corresponding author. However, the data are not publicly available due to reasons related to privacy and ethical considerations. These restrictions aim to protect the confidentiality of study participants and adhere to ethical guidelines. If you would like access to the data, please feel free to reach out to the corresponding author for further information.  
The authors declare that they have no conflicts of interest or personal relationships that could have influenced the findings reported in this paper.