SOFT MECHANOCHEMICAL SYNTHESIS OF CuO/ZnO/AL2O3 CATALYST FOR METHANOL PRODUCTION

In the work, using a set of methods for physicochemical studies, such as X-ray phase, Xray diffraction, synchronous thermal and energy -dispersion analysis, scanning electron microscopy, low -temperature adsorption -desorption of nitrogen, IR-Fourier spectroscopy, the processes occurring at the stage of mechanochemical activation and further heat treatment of the Cu(NO3)(3)center dot 3H(2)O/Zn(NO3)(3)center dot 2H(2)O/Al(NO3)(3)center dot 9H(2)O/H2C2O4 center dot 2H(2)O were studied. It has been established that at the stage of mechanochemical activation, intensive interaction of copper and zinc nitrates with oxalic acid occurs with the formation of one -water copper oxalate (CuC2O4 center dot H2O) and two-water zinc oxalate (ZnC2O4 center dot 2H(2)O). The formation of oxalates occurs at the initial moment of activation 0-15 min, which is confirmed by the data of IR spectroscopy, X-ray phase and thermal analysis. The calcination of the samples leads to the formation of the ternary oxide system CuO/ZnO/Al2O3 and the interaction of copper and zinc oxides with the formation of a solid solution. It is shown that with an increase in the MCA time, the size of the coherent scattering regions decreases from 152 angstrom for the initial sample to 115 angstrom after 60 min of treatment. In this case, the accumulation of defects in the crystal structure occurs from 0.24 to 0.72%, respectively. The value of the specific surface passes through a maximum and at 30 min of treatment is 67.1 +/- 0.3 m(2)/g. During processing, a mesoporous structure of the catalyst is formed with a total pore volume of 0.132 cm(3)/g. For the scaling process or the selection of other types of mills, the values of the supplied energy were calculated. It has been established that in order to obtain a catalyst with properties close to industrial analogs of leading foreign manufacturers, it is necessary to carry out treatment with an input energy of 79 kJ/g, and the calcination process should be carried out at a temperature of 350 degree celsius and a duration of 360 min.