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This research examines the use of coal-processing wastes of Shubarkol deposit (Kazakhstan) in obtaining useful materials such as carbon fibers. For our experiments, mesophase pitch was obtained by coal tar heat treatment at 773 K. Spinnable solution was prepared by crushing mesophase pitch into the pieces with adding poly(methylmethacrylate) as a fiber-forming material and 1,2-dichloroethane as a solvent. Elemental analysis revealed that the chemical composition of mesophase pitch (С – 91.48 %; О – 8.52 %; S – 0.00 %) showed that heat treatment up to 773 K leads to the complete removal of sulfur-containing components which affect the mesophase formation. Raman data of the obtained pitch revealed the appearance of D (1366 cm-1) and G (1605 cm-1) peaks, which are responsible for carbon materials; another peak at 2900 cm-1 shows the presence of C–H bonds. Carbon fibers with the diameter of 0.8–1.75 μm were obtained by electrospinning method in laboratory settings.

The paper represents investigation on the synthesis of carbon nanotubes by chemical vapor deposition. The products of thermal decomposition of polyethylene waste were used as source of carbon. The influence of the decomposition temperature of polyethylene on the carbon nanotubes synthesis was provided. Cenospheres, preliminarily impregnated with aqueous solutions of nickel and cobalt nitrates, were applied as catalysts for carbon nanotubes synthesis. It was determined that in the framework of research, the best results for CNTs production were achieved at polyethylene decomposition temperature of 450 °C with catalyst based on cenospheres impregnated with nickel and cobalt nitrate solutions.

This article presents results of carbon nanotubes synthesis from household high-density polyethylene waste by thermal decomposition. A specific feature of this work is that the decomposition of high-density polyethylene waste and synthesis of carbon nanotubes were carried out in one-step using three-zone chemical vapor deposition reactor. The effect of temperature in the range of 450‒550 °C on decomposition products of high-density polyethylene was investigated. The decomposition products of polyethylene wastes were investigated by IR Fourier spectroscopy. Cenospheres obtained from ash and slag waste from thermal power plants during coal combustion were used as a catalyst for the synthesis of carbon nanotubes. The cenospheres were impregnated with an aqueous solution of iron nitrate. It was found that as a result of thermal decomposition of high-density polyethylene waste at temperature of 450 °C, gaseous carbon-containing compounds are formed, which upon further heating to 800 °C lead to the formation of carbon nanotubes with a diameter of 16‒21 nm on the surface of catalyst. Physicochemical analysis showed that turbostratic carbon is almost completely absent in the formed product. Carbon nanotubes analysis was performed by scanning electron microscopy and Raman spectroscopy.

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NAS RK is pleased to announce that News of NAS RK. Series of geology and technical sciences scientific journal has been accepted for indexing in the Emerging Sources Citation Index, a new edition of Web of Science. Content in this index is under consideration by Clarivate Analytics to be accepted in the Science Citation Index Expanded, the Social Sciences Citation Index, and the Arts & Humanities Citation Index. The quality and depth of content Web of Science offers to researchers, authors, publishers, and institutions sets it apart from other research databases. The inclusion of News of NAS RK. Series of geology and technical sciences in the Emerging Sources Citation Index demonstrates our dedication to providing the most relevant and influential content of geology and engineering sciences to our community. Қазақстан Республикасы Ұлттық ғылым академиясы "ҚР ҰҒА Хабарлары. Геология жəне техникалық ғылымдар сериясы" ғылыми журналының Web of Science-тің жаңаланған нұсқасы Emerging Sources Citation Index-те индекстелуге қабылданғанын хабарлайды. Бұл индекстелу барысында Clarivate Analytics компаниясы журналды одан əрі the Science Citation Index Expanded, the Social Sciences Citation Index жəне the Arts & Humanities Citation Index-ке қабылдау мəселесін қарастыруда. Webof Science зерттеушілер, авторлар, баспашылар мен мекемелерге контент тереңдігі мен сапасын ұсынады. ҚР ҰҒА Хабарлары. Геология жəне техникалық ғылымдар сериясы Emerging Sources Citation Index-ке енуі біздің қоғамдастық үшін ең өзекті жəне беделді геология жəне техникалық ғылымдар бойынша контентке адалдығымызды білдіреді. НАН РК сообщает, что научный журнал «Известия НАН РК. Серия геологии и технических наук» был принят для индексирования в Emerging Sources Citation Index, обновленной версии Web of Science. Содержание в этом индексировании находится в стадии рассмотрения компанией Clarivate Analytics для дальнейшего принятия журнала в the Science Citation Index Expanded, the Social Sciences Citation Index и the Arts & Humanities Citation Index. Web of Science предлагает качество и глубину контента для исследователей, авторов, издателей и учреждений. Включение Известия НАН РК. Серия геологии и технических наук в Emerging Sources Citation Index демонстрирует нашу приверженность к наиболее актуальному и влиятельному контенту по геологии и техническим наукам для нашего сообщества.

Attention to carbon fiber (CF) conditioned by their unique physicochemical, mechanical and electrical properties, which makes them in demand in various fields of activity. Today there are several kinds of carbon fibers, most of which (about 90%) are made of polyacrylonitrile (PAN). Despite the fact that carbon fibers are produced from several types of different precursors, their widespread commercial use is limited by the high cost of the product. Has, many research and engineering group seek to reduce the cost of production by using cheap carbon raw materials. A likely solution to this problem is the exploitation of coal, petroleum and coal tar as an effective progenitor for CF production. This review discusses neoteric accomplishment in CF synthesis using various carbon pitches. The possibility of obtaining carbon fibers based on resin with the addition of PAN is presented, and the prospects for their use in energy storage systems and various reinforced composite materials are described in detail.