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The effect of temperature on the stability of Nujol-water emulsions

1973; Elsevier BV; Volume: 42; Issue: 2 Linguagem: Inglês

10.1016/0021-9797(73)90309-3

1095-7103

Robert D. Vold, K. L. Mittal,

Analytical Chemistry and Sensors

Abstract The rate of separation of oil from Nujol-water emulsions stabilized with sodium dodecylsulfate (SDS), cetyl pyridinium chloride (CPyCl), Tween 20 or Triton X-100 was determined over the temperature range from 5 to 30°C in an ultracentrifuge at 39,460 rpm. The emulsions were all found to be less stable at the higher temperatures, but the change in stability with temperature was such as to suggest that it is not caused primarily by changes of the viscosity with temperature. The results with SDS could be fitted to a zero-order rate expression, leading to a calculated activation energy of 9.0 kcal, but the rate of loss of oil by the other emulsions conformed to no simple rate law.