【Daily Question Question 277】2017.10.05
Thread Content
This post was last edited by liuquan1100 on 2017-10-5 08:44. [Daily Question No. 277] 2017.10.05 NH3 can cause hydrogenation cracking catalysts to produce ( ). A: Permanent poisoning B: Temporary poisoning C: Structural damage (Unless otherwise specified, all questions and answers are based on hydrogenation units.) ) The answer to the daily activity question has changed; today’s answer will be shown in subsequent questions. For management purposes, if you need to view content from a few days ago, please go through the summary post below. 2017 Q&A Summary Thread (updates have begun) http://bbs.hcbbs.com/thread-1657793-1-1.html 2017 Daily Question Summary Thread (updates have begun) http://bbs.hcbbs.com/thread-1657794-1-1.html 2016 Q&A Summary Thread (updates completed) http://bbs.hcbbs.com/thread-1597792-1-1.html (Source: Haichuan Chemical Industry Forum)
B becomes temporarily poisoned because the nitrogen in ammonia is inorganic nitrogen, and this inorganic nitrogen binds temporarily to the acidic sites in the cracking catalyst, thereby temporarily suppressing the catalyst’s activity. As the temperature rises, the ammonia molecules adsorbed on these acidic sites gradually desorb, allowing the cracking catalyst to regain its activity.