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.
Catalytic performance of Se-containing organic substances, namely methylseleninic acid, benzeneseleninic acid, phenylselenol and diphenyldiselenide, has been tested as potential catalysts for unsaturated aldehydes oxidation by hydrogen peroxide. All tested substances proved to be active in the acrolein oxidation reaction but showed different efficiency regarding used solvents and the products of reaction – acrylic acid or methyl acrylate. Optimal catalyst, reaction conditions and solvent for acrylic acid synthesis have been determined.
In the recipes of modern cosmetic, sanitary and pharmaceutical preparations, there is a large number of accessory compounds, including surface-active substances. One of the main requirements for these compounds is the efficacy, availability, lack of allergenicity, low toxicity of decomposition products and the ability to biodegradate in natural conditions. For surfactants used in the biomedical industry and pharmacy, additional requirements are put forward - biocompatibility with body tissues, bio-inertness and non-toxicity of products of their metabolism.
At pyrolysis of hydrocarbon raw materials on ethylene plants significant amounts of liquid by-products are formed. It is possible to synthesize hydrocarbon resins that are used as film forming agents in anti-corrosion and lacquer coatings based on the C9 fraction of liquid by-products of pyrolysis. The use of low temperature emulsion oligomerization can simplify the purification of the target product and whie the synthesis can be performed at low durations and temperatures.
The new data about oxidation of unsaturated aldehydes of a general structure R–CH = C(R)–CHO by molecular oxygen (in liquid and gaseous phase), peracids and hydrogen peroxide were obtained. The composition of reaction products for a series of aldehydes with different structures was determined. The dependencies of the selectivity of reaction from an aldehyde structure and oxidant type have been evaluated. It has been assumed that a stage of aldehyde interaction with peracid determines the formation of reaction products.
The peculiarity of H2O2 cleavage catalyzed with cobalt(II)acetylacetonate has been studied by the method of inhibitors in different hydrophilic solvents. As established, physical-chemical properties of reaction medium can significantly affect the rate of peroxide decomposition and catalyst oxidation as well.
Orders by monomer and initiator at polymerization of isoprene in solution of ethylacetate under the action of hydrogen peroxide have been determined. The order by monomer is equal to 1.49 ± 0.03, by initiator – 0.46 ± 0.05. Unlike polymerization in solution of isopropyl alcohol, a process in ethylacetate proceeds in homogeneous solution.
The cooligomers of isoprene and allyl alcohol under the action of hydrogen peroxide have been synthesized. Using a solvent of variable composition isopropyl alcohol–allyl alcohol showed that the cooligomer yield doesn’t depend on a ratio of solvent composition. Polymerization of allyl alcohol itself doesn’t take place. The determination of molar weights and hydroxyl group contents in the cooligomers obtained in both alcohols showed that the cooligomer obtained in the allyl alcohol has an increased functionality 3.5 against 2 in single isopropyl alcohols
In this work a detailed investigation of heterogeneous photocatalytic degradation of Navy blue HE2R 1 (NB), azo dye of the reactive class is presented using UV/TiO2/H2O2 process in the aqueous suspension under 8W low-pressure mercury vapor lamp irradiation. Here we also report about optimization of various experimental parameters such as effect of catalyst concentration, effect of substrate concentration, effect of H2O2 addition.