Document Type : Articles
Faculty of Chemistry and Chemical Technology, Al-Farabi Kazakh National University, Almaty, Kazakhstan
Laboratory of Carbon Nanomaterials and Nanobiotechnology, Institute of Combustion Problems , Almaty, Kazakhstan
Department of Metallurgical and Materials Engineering, Faculty of Chemical and Metallurgical Engineering, Istanbul Technical University, Istanbul, Turkey
This work describes the simplest method of synthesis of a carbonized cobalt catalyst based on an available natural mineral, clay activated with nitric acid, which showed high selectivity and activity in hydrogenation of acetylene to ethylene. Metal catalysts with cobalt contents of 5 %-7 % in a bentonite clay carrier from the Tonkeris deposit were synthesised. The physicochemical properties were investigated by means of X-ray powder diffraction (XRD), scanning electron microscope (SEM), IR-Fourier spectrometer. Products were analysed using a Chrom-3700 gas chromatograph and gas chromatography–mass spectrometry (Agilent 7890A/5975C). The catalytic activities of the synthesised cobalt catalysts were investigated using an installation developed for the hydrogenation of acetylene to ethylene in a gaseous medium. Carbon nanofibers with diameters ranging from 57 to 400 nm were visible on cobalt catalyst samples. Selectivity of the modified cobalt-containing catalysts for hydrogenation ranged from 89.62 % to 97 %. Ethylene conversions of 93.58 % were achieved on 7 % Co/SiAl carbonized catalyst, at an optimum temperature of 140 °C. Side reactions are activated when the temperature rises above 180 °C, so the yield of ethylene is reduced.
- This study focused on the purification of ethylene from acetylene using a catalyst made of cobalt deposited on a carbon-containing material, such as clay.
- To study the catalytic properties of the catalyst, the process of hydrogenation of acetylene with hydrogen was performed at the ratio of temperature ranges from 100 °C to 180 °C.
- Ethylene conversions of 93.58% were achieved on 7% Co/SiAl carbonized catalyst, at an optimum temperature of 140 °C.