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Chemical Bulletin of Kazakh National University
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This is an Open Access Journal

Open Access journal
ISSN (Print) 1563-0331 - ISSN (Online) 2312-7554
Published by Al-Farabi Kazakh National University

[1 journal]

Synthesis and flotation activity of reagent-collectors based on
dithiocarbonyl and phosphoryl derivatives of amino alcohols
- Authors: Nazgul Orazbaevna Akimbaeva, Indira Niyazbekovna Anuarbekova, Zhanibek Serikovich Asylkhanov, Svetlana Akhmetshakurovna Vizer, Kazbek Bekmaganbetovich Yerzhanov, Nesipbay Kuandykovych Tusipbaev, Zhadyra Amankeldievna Yerzhanova
  Abstract: Research has been carried out to study the flotation activity of new surface active substances among dithiocarbonyl and phosphoryl derivatives of monoethanolamine and diethanolamine on the gold-bearing sulphide ore of the Bestobinskoye deposit of Kazakhstan. Among the first synthesized compounds, effective collectors for selective enrichment of sulfide polymetallic gold ores were found. Sodium N-octyl-N-2-hydroxyethyldithiocarbamate (AA-41) and sodium O-2-(dimethoxyphosphoryl-2-hydroxyethylamino)ethylxanthate (GF-2) were proposed as new flotation reagents. They were tested in the flotation of gold-bearing polymetallic ore as additional collectors and showed good results, contributing to an increase in the percentage of gold extraction in the collective concentrate in comparison with the factory basic regime in which a mixture of butyl xanthate (BX) and ditiophosphate butyl ether or butyl airoflot (BAF) was used. The results of flotation tests indicate that the collective ability of AA-41 flotation agent as an additional collector is at the level of BX. While the GF-2 flotation agent as a collector in combination with BAF provides a higher gold recovery to the concentrate of 90.8%, which is higher than gold recovery when combined with BX and BAF collectors (87.7%). It should be specially emphasized that the consumption of collectors AA-41 and GF-2 in comparison with the BX consumption in the base mode is much lower, so the AA-41 consumption is 11% lower and the consumption of GF-2 is lower by 33%. Methods for synthesizing the AA-41 flotation reagents and GF-2 flotation agents were developed, and the evidence of their structure was given with the help of physicochemical methods (IRS and NMR 1Н, 13С). The principal technological scheme of the process of obtaining the flotation agent-collector GF-2, which showed the best results in the flotation of gold-bearing polymetallic ore, was developed. In the synthesis of the flotation reagent AA-41, one of the principles of "green" chemistry was used, namely, the principle 9, stating that "catalytic systems and processes (as selective as possible) are in all cases better than stoichiometric ones." The use of tetrabutylammonium iodide as catalyst in the syntheses allows shortening the reaction time, reducing the reaction temperature to room temperature, and increasing the selectivity.
  PubDate: 2017-10-19
  DOI: 10.15328/cb868
Low temperature oxidation of o-xylene with hydrogen peroxide in the
presence of vanadium xerogels
- Authors: Nurlykyz Nagashybaevna Yesmurzaeva, Roza Tursunovna Tursunova, Bagadat Samatovna Selenova, Sarkyt Elekenovich Kudaibergenov
  Abstract: The present work is dedicated to investigation of vanadium xerogels deposited on titanium oxide for the oxidation process of o-xylene by hydrogen peroxide under the mild conditions. The structure of deposited vanadium catalyst and sizes of vanadium xerogels nanoparticles were investigated by physicochemical methods. The nano-sized particles (5-8 nm) of xerogel vanadium, deposited on titanium oxide, exhibit high catalytic activity in the decomposition of hydrogen peroxide and in the oxidation of o-xylene by hydrogen peroxide under mild conditions.
  PubDate: 2017-10-05
  DOI: 10.15328/cb813
The creation of the technology of biodegradable films based on cornstarch
- Authors: Perizat Ibragimovna Urkimbayeva, Azamat Esmuratov, Raihan Kulymbetovna Rahmetullaeva, Daulet Kaldybekov, Bauyrzhan Bakytzhanuly
  Abstract: Materials able to decompose safely are very important for solving the environmental problems. In this paper the preparation conditions of biodegradable film based on polyvinyl alcohol (PVA) and starch were studied. IR-spectroscopy analysis showed that during the synthesis copolymers connect with each other due to the hydrogen bonds. The films synthesized on the basis of PVA and starch have been subjected to γ-radiation. They have shown the improved characteristics on strength, elasticity and durability in various solvents at the expense of the polymeric components sewed by hydrogen bonds. Opportunities of application of the films as a biodegradable material were shown.
  PubDate: 2017-10-05
  DOI: 10.15328/cb964
A new electrocatalytic systems based on bisorbents from rice husk
- Authors: Duisek Haisagalievich Kamysbaev, Bazarbai Alibayevich Serikbaev, Galina Sergeevna Arbuz, Dinara Alimbai, Akbayan Arin
  Abstract: The article studies results of carbon-based and amorphous silicon dioxide bisorbents (BS) synthesis. Data of the sorption characteristics of new bases for producing modified systems to use these in electrocatalysis are presented. Forpreparation SiO2/C baseas the raw material rice husk (RH) was chosen. A series of experiments was performed to optimize parameters of the RHcarbonization byvarying oftemperature and time process. The material obtained from the RH thermal destruction products was modified by the heteropoly compound (NH4)3[Co3O6Mo6O18H6] · nH2O and thermally reduced by hydrogen. The registration of the voltammetric curves was carried out at pH = 6,22 in the background electrolyte of 0,1 M Na2SO4 and pH = 4,45 in 0,1 M KC8H5O4.The potential ranges were -1,2В ÷ 1,2 V and -1,0 V ÷ 0,2 respectively. The mechanism of the electrochemical processes on these materials has been studied. It is shown that the obtained composite electrode materials exhibitelectrochemical activity in the investigated potential regions and they are characterized by the stability of redox properties. The main ways of using the obtained composites are outlined.
  PubDate: 2017-10-05
  DOI: 10.15328/cb820
Comparative hydrogenation of the sunflower oil on platinum and nickel
catalysts
- Authors: Kainaubek Toshtay, Ali Baidildaevich Auyezov, Christophe Geantet
  Abstract: The paper considers the diatomite-supported platinum catalyst (1.0 wt% Pt/D) synthesized using colloid adsorption method. The catalyst was characterized by X-ray diffraction, N2 adsorption (BET), scanning electron microscopy and transmission electron microscope. The activity of the platinum catalyst was investigated by sunflower hydrogenation at 0.5MPa hydrogen pressure at temperature range from 90°C to 130°C and compared to a commercial Ni catalyst. All of the hydrogenation reactions were terminated at iodine value between approximately 72~86. The results demonstrated that Pt/diatomite catalyst exhibited the highest activity and selectivity at low temperature than the Ni catalyst in hydrogenation processes. Physical characteristics of hydrogenated products such as melting point and solid fat content were also examined.
  PubDate: 2017-09-21
  DOI: 10.15328/cb803