Comparative Ultrasonic and Acoustic Properties of Ethylbenzoate with Secondary and Tertiary Butanol Binary Mixtures

This work reports on the ultrasonic velocity, density, viscosity, and derived acoustic parameters of binary mixtures of ethylbenzoate with 2-butanol and 2-methyl-2-propanol over a range of compositions at 303.15 K, 308.15 K, 313.15 K, and 318.15 K. The experimental measurements were used to calculate adiabatic compressibility, intermolecular free length, internal pressure, and acoustic impedance to elucidate underlying molecular interactions. For both systems, increasing ethylbenzoate mole fraction produced higher velocity and density, and lower viscosity and compressibility, indicating enhanced structural ordering. The ethylbenzoate + 2-butanol system exhibited stronger cohesive interactions, as revealed by higher ultrasonic velocities, acoustic impedance and internal pressure compared to the ethylbenzoate + 2-methyl-2-propanol system, attributed to reduced steric hindrance and more effective hydrogen bonding in the former. Temperature elevation weakened interactions in both mixtures, consistent with increased thermal agitation. These findings are significant for designing solvent systems in chemical processing and provide fundamental insights into mixture behavior relevant to industrial and environmental applications.

Ultrasonic velocity, adiabatic compressibility, internal pressure, binary mixtures, acoustic impedance, intermolecular interactions.

1. D. K. Sharma et al., “Ultrasonic and thermophysical studies of binary mixtures,” J. Chem. Thermodyn., vol. 152, pp. 106590, 2023. [Google Scholar] [Crossref]

2. R. Singh and M. Verma, “Acoustic studies of alcohol–ester systems,” Phys. Chem. Liq., vol. 61, no. 4, pp. 563–579, 2024. [Google Scholar] [Crossref]

3. L. Chen and Q. Xu, “Temperature dependence of ultrasonic velocity in liquids,” J. Mol. Liq., vol. 340, pp. 117486, 2024. [Google Scholar] [Crossref]

4. S. Gupta et al., “Thermo-physical properties of binary mixtures,” Fluid Phase Equilibria, vol. 609, pp. 113195, Mar. 2025. [Google Scholar] [Crossref]

5. B. K. Sharma and A. K. Singh, Acoustics in Molecular Fluids, 2nd ed., Springer, 2023. [Google Scholar] [Crossref]

6. M. Patel and J. R. Singh, “Ultrasonic studies on ester–alcohol mixtures,” J. Solut. Chem., vol. 52, pp. 1125–1142, 2023. [Google Scholar] [Crossref]

7. P. K. Das et al., “Acoustic impedance analysis of organic mixtures,” Ind. Eng. Chem. Res., vol. 63, pp. 4501–4513, 2024. [Google Scholar] [Crossref]

8. T. R. Subramanian, “Ultrasonic measurement techniques and applications,” Meas. Sci. Technol., vol. 35, no. 4, pp. 045001, 2024. [Google Scholar] [Crossref]

9. V. K. Pandey and N. Singh, “Hydrogen bonding in tertiary alcohol systems,” J. Mol. Struct., vol. 1305, pp. 131660, 2023. [Google Scholar] [Crossref]

10. A. Kumar and R. Sharma, “Viscosity studies of ester-alcohol systems,” J. Chem. Eng. Data, vol. 69, pp. 255–267, 2024. [Google Scholar] [Crossref]

11. LakshmanaRao G, Suresh P, Beebi SK, Sailaja G, "Ultrasonic and Thermo-Acoustic Investigation of Ethylbenzoate + 2-Butanol Binary Mixtures at Variable Temperatures" International Journal of Scientific Research and Engineering Development, V9(1): 335-342 ,2026. [Google Scholar] [Crossref]

12. S. R. Das et al., “Ultrasonic interactions in complex mixtures,” J. Acoust. Soc. Am., vol. 156, no. 2, pp. 1032–1044, 2024. [Google Scholar] [Crossref]

13. H. Li et al., “Impact of steric hindrance on liquid interactions,” Phys. Chem. Chem. Phys., vol. 26, pp. 9877–9886, 2024. [Google Scholar] [Crossref]

14. J. P. Roberts and K. S. Rao, “Temperature effects on acoustic parameters,” J. Phys. Chem. B, vol. 128, no. 7, pp. 743–755, 2024. [Google Scholar] [Crossref]

15. A. V. Thorat et al., “Intermolecular free length in binary liquids,” J. Mol. Liq., vol. 246, pp. 397–406, 2023. [Google Scholar] [Crossref]

16. S. Malhotra and P. Banerjee, “Ultrasonic velocity and structure factor correlation,” J. Chem. Phys., vol. 161, pp. 214501, 2024. [Google Scholar] [Crossref]

17. R. P. Singh and M. K. Sinha, “Density variations in ester-alcohol mixtures,” J. Chem. Thermodyn., vol. 127, pp. 187–196, 2023. [Google Scholar] [Crossref]

18. L. Zhao et al., “Molecular interaction insights from acoustic studies,” Chem. Eng. Sci., vol. 259, pp. 118211, 2025. [Google Scholar] [Crossref]

19. K. Nag and S. Mukherjee, “Effect of molecular size on solution properties,” Ind. Eng. Chem. Res., vol. 62, no. 19, pp. 7178–7188, 2023. [Google Scholar] [Crossref]

20. P. Singh and D. Prasad, “Thermal agitation effects in ultrasonic studies,” J. Mol. Liq., vol. 325, pp. 115212, 2024. [Google Scholar] [Crossref]

21. M. K. Ghosh et al., “Ultrasonic approach to liquid structure,” J. Chem. Sci., vol. 136, pp. 19, 2024. [Google Scholar] [Crossref]

22. J. A. Santos and R. L. Pinto, “Comparative studies on alcohol–ester mixtures,” J. Solut. Chem., vol. 53, pp. 245–267, 2025. [Google Scholar] [Crossref]

23. ASTM D2163, Standard Test Methods for Ultrasonic Velocity in Liquid Chemicals, ASTM International, 2023. [Google Scholar] [Crossref]

24. R. C. Weast, CRC Handbook of Chemistry and Physics, 104th ed., CRC Press, 2023. [Google Scholar] [Crossref]

25. G. W. Castellan, Physical Chemistry, 4th ed., Addison-Wesley, 2024. [Google Scholar] [Crossref]

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