What are the defining factors for wide-temperature sulfur-tolerant shift reaction?
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I often hear about wide-temperature sulfur-tolerant shift and low-temperature sulfur-tolerant shift. Could you please explain what the defining factors for these two types of shifts are?
Does no one in the forum know? I have also been paying close attention to China
Wide-temperature sulfur-tolerant shift refers to the catalyst’s wide operating temperature range, generally between 250 degrees and 460 degrees. Low-temperature sulfur-tolerant shift refers to an active temperature ranging from 210 degrees to 285 degrees. The defining factor for wide-temperature sulfur-tolerant shift and low-temperature sulfur-tolerant shift is the presence or absence of active temperature.
:lol :victory: What you said is absolutely true! OK!
What was said on the third floor is correct, but it’s just a phenomenon. Low-temperature sulfur-tolerant shift refers to CoMo-based shift catalysts using r-alumina as a carrier, which are mainly used at low pressures with shift temperatures ranging from 180 to 300 degrees ； Wide-temperature shift catalysts use magnesium-aluminum spinel or titanium-aluminum coprecipitate as carriers, with CoMo as the active component. They are used in conditions with high pressure, where the water-to-gas ratio can be either high or low; the shift temperature ranges from 200 to 400 degrees Celsius. These catalysts are relatively expensive. A pressure limit of 3.0 MPa is generally used; if the pressure is slightly below 3.0 MPa but the water vapor content is high, a wide-temperature shift catalyst must also be employed.
Agree with the view on the fifth floor. For wide-temperature sulfur-resistant catalysts, their sulfur resistance is one of the key criteria for evaluating such catalysts. However, for cobalt-molybdenum-based low-temperature shift catalysts, the view is exactly the opposite: the stronger the sulfur resistance, the worse the performance of the catalyst. Low-temperature catalysts require a certain concentration of hydrogen sulfide in the inlet gas, which is known as the allowable minimum hydrogen sulfide concentration at the inlet. The smaller this value, the wider the range of applications for the catalyst, and the better its performance. Of course, this allowable concentration of hydrogen sulfide for import is not a fixed value; it is determined by the reaction temperature and the gas-to-vapor ratio.
What specific catalyst is it? The K8-11HR catalyst is a representative of catalysts that perform well over a wide range of temperatures and water vapor ratios. It contains many components: in addition to the main material, rare earths and alkali metals are added as additives to enhance mechanical strength
Then what kind of crude syngas is suitable for sulfur-resistant low-temperature shift catalysts? What kind of applications require sulfur-resistant, wide-temperature shift catalysts?
Personally, I think it still depends on the depth of your transformation and the sulfur content in the feed gas. Sometimes, a combination of wide-temperature sulfur-tolerant shift and low-temperature sulfur-tolerant shift can be used.