Methanol Purification Version – One Question per Day 20200720
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Why is copper-based catalyst reduced before use? What is the principle? Answer: Copper in its oxidized state does not possess catalytic activity; in methanol reactions, it is the metallic copper atoms that actually play a catalytic role. Therefore, before putting copper-methanol catalysts into use, the copper oxide present in them must first be reduced to metallic copper atoms. Hydrogen reduction is used, with the equation: CuO + H2 = Cu + H2O; this reaction is highly exothermic.
Catalysts are generally titanium oxide before use; copper-based catalysts are supplied in the form of CuO, and only elemental Cu is active, so it needs to be reduced before use.
Catalysts are generally titanium oxide before use; copper-based catalysts are supplied in the form of CuO, and only elemental Cu is active, so it needs to be reduced before use.
Copper-based catalysts leave the manufacturer in the form of copper oxide. During the methanol synthesis process, the catalytic active centers are copper atoms (i.e., copper in its zero-valence state); some studies suggest that both cuprous ions and copper atoms contribute to the catalytic action. Therefore, it must be reduced with a reducing gas before use. Reduction gases generally consist of the raw gas used in factories to produce methanol; some companies, on the other hand, use hydrogen purchased from external sources. Principle: Hydrogen + carbon monoxide + copper oxide = copper (cuprous) + water + carbon dioxide.
Copper in its oxidized state does not possess catalytic activity; in methanol reactions, it is the metallic copper in its atomic form that actually plays a catalytic role. Therefore, before putting copper-based catalysts for methanol reactions into use, the copper oxide present in them must first be reduced to metallic copper in its atomic form. Hydrogen reduction is used, and the equation is CuO + H2 = Cu + H2O
The reduction of copper-based catalysts occurs in a layered manner; for the catalyst bed, it takes place from top to bottom. For each individual catalyst particle, reduction occurs gradually from the surface inward. The water generated as a result of the reduction of copper-based catalysts is known as chemical water (also referred to as crystalline water). and releases heat. The quality of reduction catalyzed by methyl isobutyl ketone determines the performance of the catalyst during operation, and it has an impact on the methanol conversion rate, consumption levels, and service life. Therefore, a reasonable reduction scheme must be adopted, and high-quality reduction operations must be carried out strictly in accordance with the reduction conditions. Currently, the two commonly used copper-based catalyst reduction methods in our country are low-hydrogen reduction and high-hydrogen reduction. The key to the reduction of copper-based catalysts is to control the reduction rate; it should not be too fast, and the temperature must be strictly controlled based on the concentrations of hydrogen and other gases. The reduction process requires a slow and steady increase in temperature as well as uniform effluent flow, in order to avoid sudden spikes in temperature and too rapid effluent discharge; otherwise, it will affect the catalyst’s activity and lifespan, and in extreme cases, the high temperature may even burn out the entire catalyst batch and damage the components inside the catalyst holder.
The reduction of copper-based catalysts occurs in a layered manner; for the catalyst bed, it takes place from top to bottom. For each individual catalyst particle, reduction occurs gradually from the surface inward. The water generated as a result of the reduction of copper-based catalysts is known as chemical water (also referred to as crystalline water). and releases heat. Currently, the two commonly used copper-based catalyst reduction methods in our country are low-hydrogen reduction and high-hydrogen reduction. The key to the reduction of copper-based catalysts is to control the reduction rate; it should not be too fast, and the temperature must be strictly controlled based on the concentrations of hydrogen and other gases. The reduction process requires a slow and steady increase in temperature as well as uniform effluent flow, in order to avoid sudden spikes in temperature and too rapid effluent discharge; otherwise, it will affect the catalyst’s activity and lifespan, and in extreme cases, the high temperature may even burn out the entire catalyst batch and damage the components inside the catalyst holder.
Catalysts are generally titanium oxide before use; copper-based catalysts are supplied in the form of CuO, and only elemental Cu is active, so it needs to be reduced before use.
Answer: Copper in its oxidized state does not possess catalytic activity; in methanol reactions, it is the metallic copper atoms that actually play a catalytic role. Therefore, before putting copper-methanol catalysts into use, the copper oxide present in them must first be reduced to metallic copper atoms. Hydrogen reduction is used, with the equation: CuO + H2 = Cu + H2O; this reaction is highly exothermic.
Catalysts are generally in an oxidized state before use. Copper-based catalysts are supplied in the form of CuO; only elemental Cu is active, so reduction is required prior to use
Copper in its oxidized state does not possess catalytic activity; in methanol reactions, it is the metallic copper in its atomic form that actually plays a catalytic role. Therefore, before putting copper-based catalysts for methanol reactions into use, the copper oxide present in them must first be reduced to metallic copper in its atomic form. Hydrogen reduction is used, and the equation is CuO + H2 = Cu + H2O