Optimization of epoxidation by using response surface methodology (RSM) based on three-level three-factorial central composite design (CCD) was used. Response percentage of relative oxirane content (%RCO) was studied to determine the optimum reaction condition for production of polyols. The predicted value of model (85 %) was excellent in accordance to experimental value (81 %).
The use of solutions of hydrogen peroxide of different concentrations, namely 1%, 17%, 35%, for cleaning the stone vazon surface from the pediment of the main entrance of the church of St. Nicholas in the village of. Vizhnyans of Zolochiv district of Lviv region. Determination of the concentration of the solution of hydrogen peroxide was carried out by permanganametometric titration in acidic medium. Solutions of hydrogen peroxide concentration of 17% and 35% were diluted during titration to a concentration of 0.3 mol / liter.