## 4 Conclusions  
Overall, 1298 Type 5 DES were inspected in a 1:1 ratio of HBA and HBD for favorable interactions with the HFC diffusormethane (R32). The results of this project were limited to the top 16 DES and analyzed further for pressure, composition, enthalpic, and EHS properties. The results indicate that the main mode of absorption within these DES with regard to diffusormethane is through van der Waals interactions. The solvents containing significant van der Waals interaction surfaces and some hydrogen bond accepting areas are deemed the most effective traits for the task. It was discovered through the compositional analysis that the HBA in pure form had the highest solubility percentage for diffusormethane. However, because these chemicals have high melting points, it is recommended for the lowest possible ratio of HBD to be added to create a low temperature melting point for the absorption of diffusormethane. Through an increase in pressure, the solubility of diffusormethane increases. MTOA was shown to be the most pressure sensitive HBA of the four studied as it contained the lowest solubility at 1 bar (18 mol/mol%) and the highest at 9 bar (86.2 mol/mol%), likely due to the size of the quaternary salt being the least symmetrical of the four, following hole theory logic. By utilizing SDS and VEGA predictive software, an EHS analysis revealed a strong potential for the 16 DES to be environmentally safe, with MTOA being the only acutely toxic substance. These insights are provided to the scientific community as evidence of the strong efficiency and safety potential of adopting DES into industrial and commercial usage for the absorption of diffusormethane. The following supporting information can be downloaded at: [[https://www.mdpi.com/article/10.3390/app13106182/s1](https://www.mdpi.com/article/10.3390/app13106182/s1)]([https://www.mdpi.com/article/10.3390/app13106182/s1](https://www.mdpi.com/article/10.3390/app13106182/s1)), Figure S1: Activity coefficients for each HBA and HBD combination computed for R32. This figure depicts a heat map containing a gradient from yellow to red. This map represents the activity coefficient (\(\mathrm{Im}\gamma\)) values of diffusormethane in DES component mixtures. Yellow represents the lower values of \(\mathrm{Im}\gamma\) while red is for higher values of \(\mathrm{Im}\gamma\). The component mixtures are referenced as Axx for HBA and Dxx for HBD along the \(x\) and \(y\) axes, respectively. The reference key for these numbers-solvents can be found in Table S1; Table S1: Chemicals studied with abbreviations and identifiers; Table S2: Charged surface area distributions per molecule in percent. Conceptualization, T.Q. and M.T.R. ; Methodology, T.Q. ; Software, T.Q. ; Validation, T.Q. ; Formal analysis, T.Q. ; Investigation, T.Q. ; Data curation, T.Q. ; Writing--original draft, T.Q. ; Writing--review & editing, M.T.R. ; Supervision, M.T.R. ; Project administration, M.T.R. ; Funding acquisition, M.T.R. All authors have read and agreed to the published version of the manuscript. This work was partially funded by the National Science Foundation under Grant No. 2123495. Not applicable. \begin{table}
\begin{tabular}{l|c c c c c c} \hline \hline  & **Persistence** & **Persistence** & **Persistence** & **Mutagenicity** & **Acute** & **BCF** & **Carcinogenicity** \\  & **Air** & **Water** & **Soil** & & **Toxicity** & **BCF** & **Carcinogenicity** \\ \hline N4 Br & g & g & b & g & g & b & b \\ BTAC1 & g & g & g & g & b & b \\ N8 Br & b & b & b & g & b & b \\ MTOA & g & g & g & r & b & b \\ PEG & g & g & g & g & g & g \\ Camphor & b & g & g & g & g & g \\ Eucalypt & b & g & g & g & g & g \\ Lidocaine & b & b & g & g & g & g \\ \hline \hline \end{tabular}
\end{table} 
Table 5: VEGA model for selected solvent components. Green indicates lower than moderate score of NFPA and/or OSHA rating; blue indicates unreliable predictions due to missing data in VEGA and no available data found in SDS database. Red indicates moderate or higher NFPA and/or OSHA rating for the property.