Title : Study of the possibility of using catalysts based on iron-ore concentrate in the decomposition of methane
Copper-containing catalysts have shown good activities for ethanol dehydrogenation to acetaldehyde. Acetaldehyde is one of the most important aliphatic chemicals. It can be used as a raw material for the production of acetic acid, acetic anhydride, ethyl acetate, butyl aldehyde, crotonaldehyde, pyridine, and many other products. The main industrial method of obtaining acetaldehyde is the oxidation of valuable ethylene in presence of aqueous solutions of chloride of expensive palladium and copper. This technology is characterized by the formation of a number of toxic chlorogenic by-products, as well as dissolved in large quantities of water, acetic acid, and crotonaldehyde. Recently, against the backdrop of stricter requirements for environmentally friendly technologies and the desire to get rid of oil dependence, interest in process of acetaldehyde synthesis by ethanol dehydrogenation increases again. In addition, it is worth noting the importance and value of hydrogen obtained in the process of catalytic dehydrogenation of ethanol along with acetaldehyde. However, in order to create a competitive technology for the production of acetaldehyde from ethanol, it is necessary to develop an effective catalyst. The activity and selectivity of these catalysts depend on the physical and chemical structure of active components. Dispersion of the metal over the support is an important factor.
In our work, the copper catalysts supported on rice husk. Rice husk is the predominant by-product in the milling process of domestic agriculture. It is usually either burned or discarded, resulting not only in resource-wasting but also in environmental pollution. As a consequence, especially in the prevailing field of material science, it makes sense to prepare rice husk (RH), which is composed of extremely amorphous silica. Silica from rice husk was obtained via hydrochloric acid leaching treatment. Silica produced from RH at a temperature of 500 to 650 ? C with a calcination time of 2.5 to 6 h is predominantly amorphous, while crystallinity is achieved when the calcination temperature rises above 700 ? C. Copper catalyst supported on rice husk was prepared by mixing copper nitrate and rice husk. These samples were dried at 723 K for 3 h. Catalyst activity tests in ethanol conversion were carried out with an automated flow catalytic unit. Results showed that the ethanol is selectivity converted to acetaldehyde when the reaction temperature is between 523-573 K. Ethanol conversion is found to be dependent on the calcination temperature of RH and Cu loading.
The results of the work may be of interest to scientists in the field of catalysis and materials science. The fundamental difference between the works is that silicon oxide obtained from rice husk is used as a carrier for copper catalysts.