【Daily Question No. 277】October 10, 2018
Thread Content
This post was last edited by Internet Invisible Man on 2018-10-10 05:54. [Daily Question No. 277] 2018.10.10: What are the mechanisms and patterns of carbon deposition on hydrogenation catalysts? In the early stage of the reaction, the amount of carbon deposit begins to increase rapidly, and the catalyst’s activity also declines quickly. As time passes, the amount of carbon deposit approaches stability, and the catalyst activity also enters a stable phase. In the later stages of the reaction, excessive carbon deposits clog the pores of the catalyst, resulting in a significant drop in its activity; therefore, an increase in temperature is needed to compensate for this. (Unless otherwise specified, all questions and answers are based on hydrogenation units.) ) Correct: 3 wealth, Incorrect: 1 wealth ； Mass posting of posts – rated based on the lowest score ； Replies that are unrelated to the answer are considered spam and will be deleted immediately. For management purposes, if you need to view content from a few days ago, please go to https://bbs.hcbbs.com/home.php?mod=space&uid=3862647&do=thread&view=me&from=space through the summary post below
In the early stage of the reaction, the amount of carbon deposit begins to increase rapidly, and the catalyst’s activity also declines quickly. As time passes, the amount of carbon deposit approaches stability, and the catalyst activity also enters a stable phase. In the later stages of the reaction, excessive carbon deposits clog the pores of the catalyst, resulting in a significant drop in its activity; therefore, an increase in temperature is needed to compensate for this.
In the early stage of the reaction, the amount of carbon deposit begins to increase rapidly, and the catalyst’s activity also declines quickly. As time passes, the amount of carbon deposit approaches stability, and the catalyst activity also enters a stable phase. In the later stages of the reaction, excessive carbon deposits clog the pores of the catalyst, resulting in a significant decrease in its activity; therefore, increasing the temperature is necessary to compensate for this
Due to the presence of acidic sites, carbon deposits gradually form on the surface of the catalyst. Carbon deposition reduces the catalyst’s activity, as carbon-forming compounds strongly adsorb onto the acidic sites, covering those active sites. Moreover, the accumulation of coke blocks the pores, preventing reactants from reaching the active sites for adsorption, which **reduces the surface utilization efficiency of the catalyst. In the early stages of the reaction, the amount of carbon deposition increases rapidly, and the catalyst’s activity declines accordingly. In the later stage, excessive carbon buildup clogs the pores of the catalyst, resulting in a significant decrease in its activity; therefore, an increase in temperature is needed to compensate for this.
Due to the presence of acidic sites, carbon deposits gradually form on the surface of the catalyst. Carbon deposition reduces the catalyst’s activity, as carbon-forming compounds strongly adsorb onto the acidic sites, covering those active sites. Moreover, the accumulation of coke blocks the pores, preventing reactants from reaching the active sites for adsorption, which **reduces the surface utilization efficiency of the catalyst. In the early stages of the reaction, the amount of carbon deposition increases rapidly, and the catalyst’s activity declines accordingly. In the later stage, excessive carbon buildup clogs the pores of the catalyst, resulting in a significant decrease in its activity; therefore, an increase in temperature is needed to compensate for this.
Due to the presence of acidic sites, carbon deposits gradually form on the surface of the catalyst. Carbon deposition reduces the catalyst’s activity, as carbon-forming compounds strongly adsorb onto the acidic sites, covering those active sites. Moreover, the accumulation of coke blocks the pores, preventing reactants from reaching the active sites for adsorption, which **reduces the surface utilization efficiency of the catalyst. In the early stages of the reaction, the amount of carbon deposition increases rapidly, and the catalyst’s activity declines accordingly. In the later stage, excessive carbon buildup clogs the pores of the catalyst, resulting in a significant decrease in its activity; therefore, an increase in temperature is needed to compensate for this.
In the early stage of the reaction, the amount of carbon deposit begins to increase rapidly, and the catalyst’s activity also declines quickly. As time passes, the amount of carbon deposit approaches stability, and the catalyst activity also enters a stable phase. In the later stages of the reaction, excessive carbon deposits clog the pores of the catalyst, resulting in a significant drop in its activity; therefore, an increase in temperature is needed to compensate for this.
In the early stage of the reaction, the amount of carbon deposit begins to increase rapidly, and the catalyst’s activity also declines quickly. As time passes, the amount of carbon deposit approaches stability, and the catalyst activity also enters a stable phase. In the later stages of the reaction, excessive carbon deposits clog the pores of the catalyst, resulting in a significant decrease in its activity; therefore, increasing the temperature is necessary to compensate for this
Answer: At the beginning of the reaction, the amount of carbon deposits starts to increase rapidly, and the catalyst’s activity also declines quickly. As time passes, the amount of carbon deposit approaches stability, and the catalyst activity also enters a stable phase. In the later stages of the reaction, excessive carbon deposits clog the pores of the catalyst, resulting in a significant drop in its activity; therefore, an increase in temperature is needed to compensate for this.
Excessively high temperature leads to coking on the catalyst
In the early stage of the reaction, the amount of carbon deposit begins to increase rapidly, and the catalyst’s activity also declines quickly. As time passes, the amount of carbon deposit approaches stability, and the catalyst activity also enters a stable phase. In the later stages of the reaction, excessive carbon deposits clog the pores of the catalyst, resulting in a significant drop in its activity; therefore, an increase in temperature is needed to compensate for this.