Abstract: Using acetone as solvent, a series of octyl phenol polyoxyethylene ether carboxylate (abbreviated as OPC n, where n is oxythylene chain length ) with different oxythylene chain length ranging from 4 to 15 are prepared from octylphenolpolyoxyethylene ether and chloroacetic acid, and their minimum concentration needed to reduce the viscosity of 7 crude oil samples from Shengli and Liaohe oilfield is measured. The result indicates that, OPC8 is the most efficient among the resultants, when mass fragment is 0.03%~0.10%, the viscosity reducing ratio of this surfactant for Shengli and Liaohe viscous oil all can be above 90%. In addition, the temperature resistance property of this viscosity reducer is studied. The result shows that, the concentration of OPC 8 changes little after being heated at 300℃ for 3 hours.

Key words: viscous oil, viscosity reducer, temperature resistance, amphoteric surfactant, steam huff and puff