Home – Home – Jornals – Chemistry for Sustainable Development 2020 number 5

Complications in the technological processes of hydrocarbon transport (an increase in viscosity, the loss of fluidity, the formation of asphalt-resin-paraffin deposits on the surface of the equipment) arising with a decrease in the temperature of the feed stream cause an increase in energy consumption and reduce the efficiency of petroleum transportation. During the recent decade, the physical methods and their combinations with chemical methods allowing a substantial improvement of the structural-mechanical characteristics of problematic oil have been under active development. One of these methods is ultrasonic treatment. The effect of ultrasonic treatment and the addition of petroleum resins on the viscosity, temperature and energy-related parameters of a 6 mass % solution of petroleum paraffin in decane (PP-d) simulating a high-paraffin petroleum system was investigated. Ultrasonic treatment (field frequency 22 kHz, intensity 18 W/cm², duration 10 min) of the PP-d solution stimulates the crystallization of the molecules of petroleum paraffin after the treatment, which causes an increase in viscosity, pour point temperature and the amount of paraffin deposits. The introduction of benzene and benzene-alcohol resins extracted from highly resinous petroleum into the PP-d solution suppresses the crystallization of petroleum paraffin molecules thus promoting a decrease in viscosity and temperature characteristics, the activation energy of viscous flow, the specific fracture energy of the disperse system, the amount of paraffin deposits, changes in the shape and structure of petroleum paraffin crystals. It is demonstrated that alcohol-benzene resins containing a larger amount of heteroatomic functional groups and longer alkyl substituents in aromatic and naphthene cycles are the best depressants of viscosity and pour point. The formation of deposits in the solution under investigation is stronger inhibited by benzene resins containing a larger amount of aromatic structures.