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南方科技大学公共卫生及应急管理学院2026级博士研究生招生报考通知(长期有效)
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xf562790119

木虫 (正式写手)

[求助] 谁知道Mars-van-Krevelen mechanism具体是什么内容???

看了很多文献提到Mars-van-Krevelen mechanism,那位大牛知道Mars-van-Krevelen mechanism,具体说下哈,谢谢了!
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shine6832

至尊木虫 (正式写手)

Dr. XU

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pzypdl: 金币+3, 谢谢回帖交流! 2012-12-14 19:57:16
多相催化根据反应类型大致可分为氧(硫)化、加氢脱氢、酸碱催化等。
氧化反应催化剂大都为过渡金属氧化物MOn,而氧化剂最普遍的就是氧气O2或空气,其反应机理为晶格氧机理,即Mars-van-Krevelen。MOn里的活泼晶格氧O与反应物反应,形成MOn-1氧空位,然后O2再在MOn-1表面吸附形成MOn。这样形成消耗-补给过程。
下图是我以前做的示意图,丙烷氧化制备丙烯

图片1.png

不沉溺幻想,不庸人自扰
4楼2012-12-14 18:37:48
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superleo8936

至尊木虫 (正式写手)

catalysis小虫一枚

【答案】应助回帖

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感谢参与,应助指数 +1
pzypdl: 金币+3, 谢谢回帖交流! 2012-12-14 08:18:49
In 1954, P. Mars (later a professor at the University of Twente) and Van Krevelen presented their findings with regard to the oxidation of aromatic compounds, such as benzene and toluene, at an international conference. The oxidation of toluene into benzaldehyde is still an important process,as it forms the first step towards creating penicillin. Mars and Van Kreve¬len used vanadium pentaoxide (V2O5) as a catalyst and patented a reaction mechanism which created the catalyst alternately in two compounds, i.e. V2O5 and V2O5-x. The catalyst splits oxygen molecules into atoms and then acts as a reservoir that can take up these atoms and then release them to form molecules. This mechanism is internationally accepted as the Mars-
Van Krevelen mechanism. It provides an outstanding example of how a catalyst can be both a ‘divorce lawyer’ and a ‘marriage broker’. The color of the catalyst reveals the condition of the surface. In an oxidized
state it is yellow-brown, but reduced it is green-blue.

good luck
签什么就是什么
2楼2012-12-14 02:03:38
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superleo8936

至尊木虫 (正式写手)

catalysis小虫一枚

【答案】应助回帖

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pzypdl: 金币+2, 谢谢回帖交流! 2012-12-14 19:56:59
forget to give you the link:

Here's one review regarding this topic.  

Journal of Molecular Catalysis A: Chemical
Volume 162, Issues 1–2, 20 November 2000, Pages 19–32
签什么就是什么
3楼2012-12-14 02:05:05
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