Measurement of Wax Melting Region

The temperature range of melting and the optical textures of phases of crude and deposit waxes were observed using an Olympus BH-2 polarizing microscope equipped with a Physitemp TS-4ER temperature-controlled hot stage (-20ºC-100ºC). The temperature corresponding to the initial melting of wax crystals until all of the visible wax crystals disappeared was observed and reported as the melting range.

Waxes were first heated to 35ºC and maintained at this temperature for 5 minutes to determine if wax crystals began to melt. The temperature was then increased an additional increment of 5ºC for each 5 minute interval. This step was repeated until all wax crystals totally melted. Because waxes were a mixture of hydrocarbon compounds, some deposit waxes melted over a large region with an uncertainty of as much as ±5ºC.