Chemical and Biological Engineering ETDs

Publication Date



A spinning-drop interfacial tensiometer was designed, built, and tested. The device is very simple, inexpensive to build, and easy to operate compared with other spinningdrop tensiometers.

The tensiometer measures the interfacial tension of liquid-liquid or liquid-vapor systems. Interfacial tensions of three systems were measured to test the device: water-heptane, glycerol-heptane, and glycerol-air.

Experimental results agree with literature values within one percent for the glycerol-heptane system. The variations among the values for the liquid-liquid systems at different rotational speeds are within six percent. Repeated experiments with different drop sizes show that drop size of the glycerol-air system may affect the results. The values at low speeds (385 to 563 rpm) are about eight percent less than the values at high speeds (953 to 1837 rpm). Possible explanations for this variation are discussed.

Document Type




Degree Name

Chemical Engineering

Level of Degree


Department Name

Chemical and Biological Engineering

First Committee Member (Chair)

David Kauffman

Second Committee Member

Richard W. Mead

Third Committee Member

Jim R. Matthews