【Q&A Question 035】2018.02.04
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【Q&A Question 035】February 4, 2018: Why cannot raw crude oil be used directly during the sulfidation of catalysts? The activity of catalysts increases during sulfidation, and using raw crude oil directly may accelerate coking of the catalysts, hindering the continuation of the sulfidation process. On the other hand, raw crude oil consumes a large amount of hydrogen, reducing the purity of the recycle hydrogen and also affecting the sulfidation process. Straight-run oil, on the other hand, consists of stable saturated hydrocarbons with few impurities, making it an ideal oil for sulfidation. (Unless otherwise specified, all Q&A questions are based on hydrogenation units.) ) Due to the limits on the number of posts in the “One Question per Day” section, “One Image per Day” has been moved to the registered devices section; you can access it through the directory I posted. For management purposes, if you need to access content from a few days ago, please go to the summary post below to enter the “My Registration Season” event – (Note: This event is currently underway in the Chemical Engineering section). https://bbs.hcbbs.com/forum.php?mod=viewthread&tid=18978 For the daily questions section related to chemical engineering technology training in 2018: https://bbs.hcbbs.com/forum.php?mod=viewthread&tid=1888971 For the daily image summary section related to registration equipment in 2018: https://bbs.hcbbs.com/forum.php?mod=viewthread&tid=1888970 For the Q&A section related to hydrogen production and hydrogenation technologies in 2018: https://bbs.hcbbs.com/forum.php?mod=viewthread&tid=1888968 For the daily questions section related to LNG technology in 2018: https://bbs.hcbbs.com/forum.php?mod=viewthread&tid=1888973 For the Q&A section from 2017 (updates have started): https://bbs.hcbbs.com/thread-1657793-1-1.html For the daily questions section from 2017 (updates have started): https://bbs.hcbbs.com/thread-1657794-1-1.html For the daily image summary section from 2017: https://bbs.hcbbs.com/forum.php?mod=viewthread&tid=1875160 For the list of daily questions related to LNG in 2017: https://bbs.hcbbs.com/forum.php?mod=viewthread&tid=1804162 For the Q&A section from 2016 (updates are complete): https://bbs.hcbbs.com/thread-1597792-1-1.html
Raw materials have high contents of S, N, O, and olefins, and are unstable in nature. The bed temperature is difficult to control.
The activity of the sulfurized catalyst is extremely high; if it is used with crude oil of poor quality, carbon deposition will occur immediately, leading to a significant drop in catalyst activity. Therefore, jet fuel or straight-run diesel must be used to stabilize its initial activity, thereby reducing the catalyst’s activity to an appropriate level and extending its service life. Distilled aviation fuel is used as the stabilizing oil; due to its very low olefin content, it hardly causes carbon deposition on the surface of the catalyst once it enters the reaction system, so it provides little or no effect in terms of initial activity stabilization. The quality of straight-run diesel lies between that of aviation fuel and coker diesel; during the initial stabilization phase, a certain amount of carbon deposition can form on the surface of the catalyst, thereby appropriately reducing its activity and ensuring temperature control during normal operation.
The catalyst becomes more active during sulfidation; using crude oil directly may accelerate catalyst coking and hinder the continuation of the sulfidation process. On the other hand, crude oil consumes a large amount of hydrogen, reducing the purity of the recycled hydrogen and thus affecting the sulfidation process as well. Straight-run oil, being stable saturated hydrocarbons with few impurities, is an ideal oil for sulfidation.
The catalyst becomes more active during sulfidation; using crude oil directly may accelerate catalyst coking and hinder the continuation of the sulfidation process. On the other hand, crude oil consumes a large amount of hydrogen, reducing the purity of the recycled hydrogen and thus affecting the sulfidation process as well. Straight-run oil, being stable saturated hydrocarbons with few impurities, is an ideal oil for sulfidation.
The catalyst becomes more active during sulfidation; using crude oil directly may accelerate catalyst coking and hinder the continuation of the sulfidation process. On the other hand, crude oil consumes a large amount of hydrogen, reducing the purity of the recycled hydrogen and thus affecting the sulfidation process as well. Straight-run oil, being stable saturated hydrocarbons with few impurities, is an ideal oil for sulfidation.
The activity of the sulfurized catalyst is extremely high; if it is used with crude oil of poor quality, carbon deposition will occur immediately, leading to a significant drop in catalyst activity. Therefore, jet fuel or straight-run diesel must be used to stabilize its initial activity, thereby reducing the catalyst’s activity to an appropriate level and extending its service life. Distilled aviation fuel is used as the stabilizing oil; due to its very low olefin content, it hardly causes carbon deposition on the surface of the catalyst once it enters the reaction system, so it provides little or no effect in terms of initial activity stabilization. The quality of straight-run diesel lies between that of aviation fuel and coker diesel; during the initial stabilization phase, a certain amount of carbon deposition can form on the surface of the catalyst, thereby appropriately reducing its activity and ensuring temperature control during normal operation.
The catalyst becomes more active during sulfidation; using crude oil directly may accelerate catalyst coking and hinder the continuation of the sulfidation process. On the other hand, crude oil consumes a large amount of hydrogen, reducing the purity of the recycled hydrogen and thus affecting the sulfidation process as well. Straight-run oil, being stable saturated hydrocarbons with few impurities, is an ideal oil for sulfidation.
The activity of the sulfurized catalyst is extremely high; if it is used with crude oil of poor quality, carbon deposition will occur immediately, leading to a significant drop in catalyst activity. Therefore, jet fuel or straight-run diesel must be used to stabilize its initial activity, thereby reducing the catalyst’s activity to an appropriate level and extending its service life. Distilled aviation fuel is used as the stabilizing oil; due to its very low olefin content, it hardly causes carbon deposition on the surface of the catalyst once it enters the reaction system, so it provides little or no effect in terms of initial activity stabilization. The quality of straight-run diesel lies between that of aviation fuel and coker diesel; during the initial stabilization phase, a certain amount of carbon deposition can form on the surface of the catalyst, thereby appropriately reducing its activity and ensuring temperature control during normal operation.
The catalyst becomes more active during sulfidation; using crude oil directly may accelerate catalyst coking and hinder the continuation of the sulfidation process. On the other hand, crude oil consumes a large amount of hydrogen, reducing the purity of the recycled hydrogen and thus affecting the sulfidation process as well. Straight-run oil, being stable saturated hydrocarbons with few impurities, is an ideal oil for sulfidation.
Answer: The catalyst becomes more active during sulfiding. Using crude oil directly may accelerate catalyst coking, hindering the continuation of the sulfiding process. On the other hand, crude oil consumes a large amount of hydrogen, reducing the purity of the recycle hydrogen and also affecting the sulfiding process. Straight-run oil, being stable saturated hydrocarbons with few impurities, is an ideal oil for sulfiding.