Neopentane conversion over Pd/γ-Al2O3
Neopentane conversion over Pd/γ-Al2O3
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Pd/γ-Al2O3 上的新戊烷转化
DOI：
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发表时间：
1995
期刊：
影响因子：
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通讯作者：
J. Pielaszek
中科院分区：
文献类型：
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作者：
W. Juszczyk;D. Lomot;Z. Karpiński;J. Pielaszek
X-射线衍射表明，在600℃高温还原过程中，无氯Pd/γ-Al_2O_3发生部分转变为Pd-Al_2O_3合金，这与其他研究结果相一致[9]。这一演化过程似乎对新戊烷与氢反应的催化行为有很大影响：异构化选择性从-lt；20增加到∼80%。同时，活化能从∼60降至∼22千卡/摩尔。这些变化可以通过在500℃下氧化，然后在300℃下还原来逆转。残留氯(前PdCl2前体)的存在似乎抑制了Pd诱导的Al_2O_3还原，导致Pd-Al合金的形成。
X-ray diffraction showed that during high temperature reduction at 600°C, chlorine-free Pd/γ-Al2O3 undergoes partial transformation to a Pd-Al alloy, which confirms results of other studies [9]. This evolution appears to have a large effect on the catalytic behaviour in the reaction of neopentane with hydrogen: the selectivity towards isomerization increases from <20 up to ∼80%. At the same time, the activation energy drops from ∼ 60 to ∼ 22 kcal/mol. These changes can be reversed by oxidation at 500°C followed by reduction at 300°C. The presence of residual chlorine (ex-PdCl2 precursor) appears to inhibit the Pd induced reduction of Al2O3 leading to Pd-Al alloy formation.