Methanol synthesis catalyst
Thread Content
Methanol synthesis catalysts fall into two main categories: one is zinc-based catalysts based on alumina as the main component； Another type is copper-based catalysts based on copper oxide. Zinc-based catalysts are generally only suitable as catalysts for methanol synthesis at high temperatures (380°C) and high pressures (32 MPa), whereas copper-based catalysts can exhibit considerable reaction activity at a pressure of 5 MPa and lower temperatures (240°C). According to electronic catalysis theory, both zinc oxide and copper oxide possess a semiconductor structure (that is, in the ion shell layers that form the lattice in semiconductors, certain electrons can be easily excited from their normal energy levels when the temperature rises; these electrons give rise to what is known as an electron gas existing between the various nodes of the lattice, as well as electron holes formed due to these free electrons, resulting in uneven energy distribution on the surface of the material). This is why they exhibit catalytic activity. Based on the experiments, Nata believes that the reaction is a three-molecule reaction between the adsorbed carbon monoxide and hydrogen:
Friend! Could the information provided be more detailed? Our methanol plant is about to start up; could you provide more information on catalyst reduction? Thank you! ! ! ! ! ! ! ! ! ! ! ! !
Please be more detailed; I am discussing the mechanism by which catalysts participate in methanol reactions.
Reactions will not be written here; they can be uploaded as attachments. If your level is not high enough, reply to others’ posts to earn points, and once you reach level 3, you’ll be able to post your own messages. People will be very interested in the content of your posts, so work hard to upgrade your level
Please take a look at my topic: Temperature-induced reduction of methanol synthesis catalysts； I hope this will be helpful to you.
I’ll say something too. The catalysts used in our factory are copper-based catalysts. After loading is complete, heating begins, using 3.8 MPa steam as the heat source. Starting from room temperature, up to 60°C, 120°C, and 170°C, with a constant temperature for 1 hour. H2 is started to be introduced, entering the reduction stage. Raise to 230°C and maintain at a constant temperature. Carry out reduction at an increasing temperature; note that the flow rate of the output fluid and the temperature increase should be gradual, to prevent sudden spikes in temperature, as this can cause the catalyst to break down and get damaged. During temperature-raising reduction, if any abnormalities occur, the operating conditions must be adjusted promptly.
If you need anything, feel free to leave a message; let’s discuss it together!
Whoever has information on the temperature rise and reduction process related to methanol synthesis catalysts, as well as the principles behind it, please send it to me; I would be very grateful. Email: 459161632@qq.com
Regarding the temperature-induced reduction of catalysts, various manufacturers provide fairly detailed information on this topic; however, there is not much information available on the principles behind catalyst activity. I hope the original poster can provide more detailed explanations for everyone’s learning purposes.
Currently, many copper-based catalysts are in use, mainly XNC-98 and C307
Friend, could you explain in more detail: what is the mechanism by which copper-based catalysts absorb hydrogen sulfide? Thank you!
The device is about to start operating; I hope to learn from all of you seniors at HaiChuan. Thank you everyone!
Why can’t the catalysts in our factory last very long?
It is hoped to be helpful for the temperature-induced reduction of methanol synthesis catalysts
Could you please provide the passivation reduction method using C307? My email address is lzd5198@yahoo.com.cn
Catalyst manufacturers will provide detailed instructions for use.
Basic composition of the C207 type bidentate catalyst: It is primarily composed of oxides of copper, zinc, and aluminum, with copper oxide (CuO) accounting for 38–42%, zinc oxide (ZnO) 38–43%, and aluminum oxide (Al2O3) 5–6%. In addition, it contains small amounts of graphite and moisture. Usage characteristics: 1. The catalyst must be reduced before use; a reduced catalyst will burn rapidly when exposed to air. Therefore, care must be taken to prevent air from entering during use or during shutdown for maintenance. 2. The active temperature range of the catalyst is 220–300°C, with the optimal range being 230–280°C. 3. Sulfur, chlorine, oils, hydroxyl iron, unsaturated hydrocarbons, etc., can all poison the catalyst; therefore, the total sulfur content in the gas entering the tower must be below 0.1 mg/m3. There should be less chlorine than sulfur, and impurities such as oils should also be removed as much as possible. Reduction principle: In the C207 type diol catalyst, under low-temperature and low-hydrogen reduction conditions, only copper oxide is reduced, while the oxides of zinc and aluminum are not reduced. The reduction of copper oxide is an exothermic reaction: CuO + H2 = Cu + H2O + 86.7 KJ/mol. The water yield resulting from heating and reduction is approximately 20% of the catalyst’s weight (including both physical and chemical water).
Our factory uses copper-based catalysts to absorb hydrogen sulfide from syngas in the purification tank. Is it copper oxide that reacts with hydrogen sulfide, or some other substance? Could you provide more information on catalysts? Thank you!