| Methanol is one of the most important basic substances in organic chemical. Also, it is a fundamental material in C1 industry. It is mainly used to produce formaldehyde, acetic acid, methyl chloride, methyl ammonium, dimethyl sulfate grease and many other organic products. And it is one of the based raw materials for pesticides and medicine. The requirement for kinds of clean energy is infinitely increasing, because of frequent outbreaks of energy crisis and the worsening environment, recently. Methanol has some advantageous characteristics, such as clean, nontoxic, pollution-free, and so on. Because of these above, methanol attracted more and more attention since the 1960s. As a replacer, methanol can be blended with diesel or gasoline to reducing exhaust pollution, after been processed. Energy consumption in China is an urgent problem. Researches on carrying out new methanol synthesis catalysts have broad application prospects and far-reaching significance.Copper-based catalysts mainly prepared by co-precipitation generally, in commercial. The conventional stirred tank reactor (CSTR) was used widely to prepare the catalysts, but the CSTR has some disadvantages in device structure and other factors. It will waste high energy consumption to achieving microcosm uniform mixing, therefore it not adapts to commercial production. In addition, products can not be removed from the reactor in time, which made the low rate of reaction inequality and dispersion between CuO and ZnO. All of these induced asymmetrical particle size and uneven distribution of active components.The high gravity co-precipitation (HGCP) can solve these problems commendably. It makes uniform mixing of reactants within the micro-moment easily. Further more, the nucleation zone is separate from the crystal growth area, which makes the crystal growth area be placed in macro-mixed zone, completely. The catalyst prepared by HGCP has uniformly component distribution, a narrow range of particle size and an excellent crystal can be controlled by the reaction. The HGCP provides a novel method to explore the CuO/ZnO/Al2O3 catalysts.The CuO/ZnO/Al2O3 catalysts, with various proportions of Cu arid Zn, were prepared by High Gravity Co-precipitation method (HGCP). The characterizations methods, such as X-ray diffraction (XRD), thermogravimetric-differential scanning calorimeter (TG-DSC), infrared spectroscopy (IR), N2 adsorption-desorption and scanning electron microscopy (SEM), etc. were carried out to study the phase composition, particle size, pore structure, and surface morphology of the catalysts. Comparing to current catalysts prepared by conventional stirred tank reactor, the catalysts prepared by High Gravity Co-precipitation Method exhibited smaller average particle size, higher dispersion of copper and zinc, moreover, higher specific surface area. Meanwhile, the activity test of methanol synthesis was used from CO+H2 under the pressure of 5.0 MPa. The results of activity tests indicated that catalysts prepared by high gravity co-precipitation method had higher activity than that prepared by traditional method from the temperature between 220℃to 250℃. Especially, the catalyst made of mole ratio of n (Cu)/n (Zn)/n (Al)= 4.5/4.5/1, which had the highest catalytic activity and the greatest extent dispersion of CuO/ZnO, and the conversion rate of CO reached to35.3%. Catalysts made by High Gravity Co-precipitation method were better than the conventional ones in overall performance. It can fit the requirement of industrialization, and will have good application prospects.
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