【Q&A Question 028】2017.01.28
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This post was last edited by 955559 on 2017-7-21 at 12:37. [Q&A Question No. 028] Why, during the pre-sulfurization of a catalyst on 2017.01.28, must the bed temperature not exceed 230 degrees Celsius before hydrogen sulfide penetrates the catalyst? The reference answers will be visible after responding; points are awarded by identifying the key points. (Unless otherwise specified, all questions and answers are based on hydrogenation units.) This is because during the catalyst pre-sulfidization process, before hydrogen sulfide penetrates the catalyst, if the temperature is above 230 degrees Celsius, the catalyst in its oxidized state will be reduced to its metallic form, thereby reducing the catalyst’s activity and affecting the efficiency of its sulfidization. New Normal Cup – Voting for the Top 10 Members of HaiChuan in 2016 is now underway; choose the member you care about the most (please cast your valuable vote for those from the Petrochemical Division). http://bbs.hcbbs.com/thread-1667649-1-1.html Summary post of Q&A questions for 2017 (updates available now). http://bbs.hcbbs.com/thread-1657793-1-1.html Summary post of daily questions for 2017 (updates available now). http://bbs.hcbbs.com/thread-1657794-1-1.html Summary post of Q&A questions from 2016 (all updates completed). http://bbs.hcbbs.com/thread-1597792-1-1.html Third round of selection for outstanding management members at HaiChuan. http://bbs.hcbbs.com/thread-1655902-1-1.html “Creative Ideas for Energy Saving” campaign in the Petrochemical Division. http://bbs.hcbbs.com/thread-1666758-1-1.html Xiaomi phones are up for grabs. Summary post collecting chemical industry technical materials from the “Petrochemical Section”. http://bbs.hcbbs.com/thread-1654603-1-1.html Many prizes await you (Source: HaiChuan Chemical Forum)
The catalyst reacts with hydrogen, undergoing transition reduction
Before 230 degrees, the hydrogen sulfide concentration in the system is low; hydrogen will reduce the catalyst, ultimately affecting its activity
Because during the catalyst presulfurization process, before hydrogen sulfide penetrates the catalyst, if the temperature is above 230°C, the catalyst in its oxidized state will be reduced to metallic form by hydrogen, thereby reducing the catalyst’s activity and affecting the sulfurization process.
Prevent hydrogen from reducing the sulfide-form metal in the catalyst to elemental metal at high temperatures
This is because during the catalyst pre-sulfidization process, before hydrogen sulfide penetrates the catalyst, if the temperature is above 230°C, the catalyst in its oxidized state will be reduced to metallic form by hydrogen, thereby reducing the catalyst’s activity and affecting the sulfidization process.
This is because during the catalyst pre-sulfidization process, before hydrogen sulfide penetrates the catalyst, if the temperature is above 230°C, the catalyst in its oxidized state will be reduced to metallic form by hydrogen, thereby reducing the catalyst’s activity and affecting the sulfidization process.
Preventing the catalyst from being reduced also serves to prevent excessive temperature rise and overheating
This is because during the catalyst pre-sulfidization process, before hydrogen sulfide penetrates the catalyst, if the temperature is above 230°C, the catalyst in its oxidized state will be reduced to metallic form by hydrogen, thereby reducing the catalyst’s activity and affecting the sulfidization process.