Студенттер мен жас ғалымдардың «фараби әлемі» атты халықаралық ғылыми конференциясы
PROCESS OF CATALYTIC REFORMING OF METHANOL INTO HYDROGEN-
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Сборник конф Фараби Әлемі 2023 химфак-печать
| PROCESS OF CATALYTIC REFORMING OF METHANOL INTO HYDROGEN-
CONTAINING FUEL MIXTURES Assylbekov Y.B. 1 , Zhylkybek M. 1 , Kassymkhan K. 2 , Tungatarova S.А. 1,2 Scientific supervisor: Dr. Sс., Professor Tungatarova S.А. 1 Al-Farabi Kazakh National University Almaty, Kazakhstan 2 D.V. Sokolsky Institute of fuel, catalysis and electrochemistry, Almaty, Kazakhstan yer-asyl@mail.ru Transformation of initial chemical compound into a hydrogen-containing gas is carried out, as a rule, using catalytic processes. A variety of systems for producing hydrogen from hydrocarbons and alcohols for energy are being developed. We chose methanol forour process because of the fact that, unlike many other organic fuels, methanol has a relatively low temperature 250–300°C of catalytic conversion to hydrogen and CO 2 , which greatly simplifies the design of reactor. The method we have stopped our choice on is catalytic steam reforming. Steam reforming of methanol is an endothermic reaction and requires supply of heat to the reaction zone (1): CH 3 OH + H 2 O = CO 2 + 3H 2 (1) ∆ r H 0 = -49.4 kJ*mol -1 The use of copper-containing catalysts makes it possible to carry out the process of steam reforming at a temperature of 200-300 °C. In this case, for 100% methanol conversion, the contact of reagents with the catalyst layer with a duration of no more than 0.1–1 sec was sufficient. For our process a high-efficiency and stable Cu-Ce-Al 2 O 3 catalyst was prepared by taking the activated alumina as the carrier. The preparation factors that affected the catalytic activity of Cu- Ce-Al 2 O 3 were investigated. Optimal working conditions, and different ratio of components were researched. Characterization results show that Cu and Ce are successfully supported on the surface of the activated alumina support and mainly exist in the form of oxides (e.g., CuO and CeO 2 ). The loading of metal led to a larger specific surface area and pore volume. Analytically pure copper nitrate hexahydrate (Cu(NO 3 )2ꞏ6H 2 O), cerium nitrate hexahydrate (Ce(NO 3 ) 3 ꞏ6H 2 O) were used for preparing the catalyst. The catalyst was prepared by using the equal amount impregnation method. Cu(NO 3 ) 2 -6H 2 O and Ce(NO 3 ) 3 -6H 2 O were weighed on an electronic balance, and a 0.8 mol/L concentration of the metal element active component precursor solution was prepared, controlling the molar ratio of Ce:Cu from 3:1 to 1:3. The pretreated activated alumina was placed in a conical flask, and the precursor solution was poured in until it was submerged in the activated alumina. The conical flask was shaken in a water bath shaker for 2 h, and the water bath temperature was set at 25 °C. The supporter was dried at 110°C for 12 h. The catalyst was roasted in a muffle furnace at a controlled roasting temperature of 300–550°C for 2–6 h. The Cu-Ce-Al 2 O 3 catalyst was produced when the temperature cooled. When Ce:Cu = 1:2, the roasting temperature is 500°C, and the roasting time is 5h, the elements Cu and Ce can be converted to the corresponding metal oxides better, and the catalytic activity of the catalyst is higher. «Фараби Әлемі» атты студенттер мен жас ғалымдардың халықаралық конференциясы 264 жүктеу/скачать 2,6 Mb. Достарыңызбен бөлісу:
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