The Effect of a Hydrocarbon Fragment in a Molecule on Depressant Activity of Resins

The effect of resins on solidification of paraffin solutions has been studied by vibration viscosimetry. This technique was used for studies of coagulating liquids, since the sample structure is less affected by mechanical oscillations compared to traditional rotary and linear shears. The installation developed for studies of thermo-induced phase transitions and the measurement procedure are described. The viscosimetric technique allows continuous registration of rheological properties with changing temperature, and has proved to be quite sensitive to small amounts of resins in model paraffin solutions. Measurements have been performed for resins extracted from methane-naphtene crudes of various West Siberia oil deposits. Dependencies of viscosity on temperature have been measured and are presented below for various concentrations of resins (up to 3 %) in paraffin solutions. It is demonstrated that increase of resin concentration results in a shift of the inflexion point on the viscosity-temperature curve to lower temperatures. A positive correlation has been found between depressant activity and average dimensions of aliphatic fragments of the resin molecu.