Synthesis of silica/metatitanic acid nanocomposite and evaluation of its catalytic performance for aquathermolysis reaction of extra-heavy crude oil

A lipophilic silica/metatitantic acid (denoted as SiO2/H2TiO3) nanocomposite was synthesized by hydrothermal reaction with surface-modified SiO2 as the lipophilic carrier. As-synthesized SiO2/H2TiO3 nanocomposite was used as a catalyst to promote the aquathermolysis reaction of extra-heavy crude oil thereby facilitating the recovering from the deep reservoirs at lowered temperature. The catalytic performance of the as-synthesized SiO2/H2TiO3 catalyst for the aquathermolysis reaction of the heavy oil at a moderate temperature of 150 degrees C was evaluated in relation to the structural characterizations by TEM, FTIR, XRD and FESEM as well as the determination of the specific surface area by N-2 adsorption-desorption method. Findings indicate that as-synthesized SiO2/H2TiO3 nanocomposite exhibits an average size of about 20 nm as well as good lipophilicity and dispersibility in various organic solvents; and it shows good catalytic performance for the aquathermolysis reaction of the extra-heavy oil extracted from Shengli Oilfield of China. Namely, the as-synthesized SiO2/H2TiO3 catalyst is capable of significantly reducing the viscosity of the tested heavy oil from 58,000 cP to 16,000 cP (referring to a viscosity reduction rate of 72.41%) at a mass fraction of 0.5%, a reaction temperature of 150 degrees C and a reaction time of 36 h, showing potential application in downhole upgrading heavy crude oils. (C) 2015 Science Press and Dalian Institute of Chemical Physics. All rights reserved.