摘要
本文广泛研究了s-,d-,f-类金属离子在乙苯液相氧化中的催化性能。发现金属膏子在液相氯化反应中的催化活性变化规律和其在多相催化氧化反应中相似,即与金属氯的成键能力有关;对中间产物乙苯过氧化氢的选择性则取决于离子的氯化还原电位。f-类元素的铈离子具有独特的催化性能,其催化活性与d-类金属离子相似,而其对乙苯过氧化氢的选择性则接近于s-类金属离子。根据实验结果,提出了络合—链锁反应机理:金属离子首先和分子氧络台生成氧的活性络合物,然后和反应物分子相互作用,生成自由基并按链锁反应机理继续进行。
The catalytic action of s-, d-, f- metal ions in the liquid phase oxidation of ethylbenzene was investigated. It was found that the variation pattern of catalytic activity of metal ions in the liquid phase oxidation was similar to that in heterogeneous oxidation, and as is generally accepted, this could also be related to the bond energy between metal and oxygen. The selectivity towards intermediates—ethylbenzene hydroperoxide could be attributed to the redox potential of metal ions. The cerium ion of f- element behaved extraordinarily, its activity was similar to that of d-metal ions, but its selectivity towards ethylbenzene hydroperoxide approximated to that of s-metal ions.@@@@Based on these experimental results, a complexing-chain reaction mechanism was proposed, the metal ion reacted with oxygen molecule forming active dioxygen complex at first, which in turn interacted with substrate producing radicals and then the reaction proceeds according to the well-known chain reaction mechanism.
出处
《燃料化学学报》
EI
CAS
1981年第2期130-139,共10页
Journal of Fuel Chemistry and Technology
