The SiO2-CaCl2 hybrid porous materials were prepared by the sol-gel method. This process was conducted by the hydrolysis and condensation of Tetraethyl orthosilicate (TEOS) by replacement of ethanol from alcogel and drying at the ambient temperature to obtain xerogel structure. The alcogel samples were synthesized from TEOS, EtOH, H2O, HCl, NH4OH and CaCl2, while the total molar ratio of the co...

Silica nanoparticles were synthesized by chemical methods from tetraethylorthosilicate (TEOS), polyethylene glycol 5% and hydrochloric acid 0.001 N. The sol-gel process was applied for the preparation of nano silica gel. This method is hydrolysis and condensation reactions of TEOS as precursor of silica. The optimal synthesis conditions for the preparation of silica nanoparticles were obtained ...

The dried nitrate-urea gels exhibit the combination of autoicatatric combustion behavior and ultrasonic, whichcan be used to synthesize the nanocatalyst ferrite powders. Cu and Ni Unites nanocatalyst powders sithcomposition of Caned], and NiFe204 were synthesized by a sol-gel auto catalnic combustion process. Themolar ratio between metal ions and urea was 11.2. The sob gel process was done at 8...

Mature oilfields usually encounter the problem of high watercut. It is practical to use chemical methods for water-shutoff in production wells, however conventional water-shutoff agents have problems of long gelation time, low gel strength, and poor stability under low temperature and high salinity conditions. In this work a novel polymer gel for low temperature and high salinity reservoirs was...