Université Lille Nord de France, Université Lille 1, ENSCL, EA 4478, Chimie Moléculaire et Formulation, 59655 Villeneuve d'Ascq Cedex, France.
Chemistry. 2012 Nov 5;18(45):14352-8. doi: 10.1002/chem.201201799. Epub 2012 Sep 20.
Decyl-, dodecyl-, and tetradecyltrimethylammonium cations were combined with the catalytic polyoxometalate PW(12)O(40) anion to give spherical and monodisperse nanoparticles that are able to stabilize emulsions in the presence of water and an aromatic solvent. This triphasic liquid/solid/liquid system, based on a catalytic surfactant, is particularly efficient as a reaction medium for epoxidation reactions that involve hydrogen peroxide. The reactions proceed at competitive rates with straightforward separation of the phases by centrifugation. Such catalytic "Pickering" emulsions combine the advantages of heterogeneous catalysis and biphasic catalysis without the drawbacks (e.g., catalyst leaching or separation time).
癸基、十二烷基和十四烷基三甲基铵阳离子与催化多金属氧酸盐PW(12)O(40)阴离子结合，形成能够在水和芳香族溶剂存在下稳定乳液的球形和单分散纳米粒子。这种基于催化表面活性剂的三相液体/固体/液体体系在涉及过氧化氢的环氧化反应中是一种特别有效的反应介质。反应以竞争性速率进行，通过离心很容易实现相的分离。这种催化“Pickering”乳液结合了多相催化和两相催化的优点，而没有缺点（例如，催化剂浸出或分离时间）。
