Chemistry and chemical technologies / 6. Organic chemistry

 
UDC 541.128.66.097

Ph.D. Assilbekova AD, Ph.D. Shagraeva B.B., Aldazhumanova A.T.

International Kazakh-turcish University H. Yasavi
,
Academic Innovation University, Shymkent, Kazakhstan


 Electrokinetic and catalytic properties of copper-aluminum suspension

 

It is well known that the copper-aluminum alloys / 1 / and the powders after leaching are often used in the form of suspensions as catalysts in the synthesis of polyols - polyols. Polyols are widely used in chemical, food and medical industries /2/. Sugar alcohols are used in the manufacture of confectionery, cosmetics, surface-active substances. Sugar alcohols can be used in the manufacture of food products subjected to heat treatment, but should be considered in the production of various food products that they dissolve in water occurs with heat absorption. When mixing a number of sugar alcohols observed a synergistic effect, giving rise sweet mixture. For example, a mixture of 37% xylitol and 63% maltitol syrup used in the production of marmalade, a mixture consisting of 40% and 60% sorbitol, xylitol, has a sweetness equal to the sweetness of sucrose, is used in the manufacture of chewing gum. Sorbitol is not toxic, sweet taste, does not cause rapid changes in the amount of sugar in the blood and does not cause more insulin the pancreas. In certain doses allowed diabetics.

Many modern technological processes in chemical, petrochemical industry, energy sector related to the use and processing of liquid to gas, copper and aluminum catalysts. As the copper-aluminum catalysts are frequently used metal alloys eight groups with aluminum and metal oxide composition. These copper-aluminum alloy catalysts are formed by the removal of inert additives leaching of aluminum.
Selection and rational use of copper-aluminum catalysts is only possible if there is sufficient knowledge of the mechanisms of surface transformation. Therefore, the study of the elementary stages of the reacting molecules and their interaction with the surface of copper-aluminum catalysts are of great both scientific and practical interest.
         Dispersed system should be used in a reactor with intensive movement or circulation of the catalysts. For the hydrogenation of monosaccharides have been used copper and aluminum catalysts. It was noted that the catalytic properties of copper-aluminum catalysts mainly depends on the composition and nature of the initial catalyst.
          In this regard, raising the technical level and economic indicators of the production of polyols is an urgent task today. Despite the apparent homogeneity of each grain separately is a heterogeneous system mikroingredientov. From this position should also consider their behavior in various chemical and catalytic processes. Identifying common patterns will provide opportunities predict various properties of solid sols, the synthesis or replacing them with affordable, cost-effective components.
   
     In the present study, we investigated the relationship between the catalytic characteristics and electrokinetic potential of copper-aluminum suspension. The value of the zeta potentials of suspensions lower in aquatic than in isopropanol. For example, for  Fe zeta potential in% Cr and Cu-5 % Al), Cu-5 %suspensions of Cu - (50  water have values 22, 44 and 32 mV, and in isopropanol, 30, 49 and 34 mV, respectively.
   
      Suspension with a water medium values of the zeta potential of 22 - 30 mV are prone to hydrogenolysis reaction, and dispersed redundant system with a value of 30 to 50 mV show catalytic properties in reactions of hydrogenolysis and in the hydrogenation.

Literature
1. Ashirov A., Isaev TA, Birdiyarova AM, Kedelbaev B.Sh. Gilrirovanie and hydrogenolysis of carbohydrates. Proc. Scientific and Technical. and teaching and methodical. Conf. Aktualnae problems in science, technology, manufacturing and education, the Shymkent, 1993, v. 1, pp. 57-58.
2. Kedelbaev B.Sh. Development of a method of synthesis of xylitol on copper catalysts. M.: 1991, 21p. Abstract of Thesis. At soisk. uch. step. kand.him.nauk.


                  

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