Polymerization of Light Olefins over Nickel Oxide–Silica-Alumina

Catalysis in the Upgrading of Fischer–Tropsch Syncrude

“…138,139 In the context of FTS, it is worthwhile pointing out that these catalysts are sensitive to water and deactivation has been reported when NiO/SiO 2 -Al 2 O 3 catalysts adsorb as little as 0.5% moisture. 131 This is contrary to the behaviour of silica-alumina catalysts, which are activated by the addition of small amounts of water. 140-142…”

“…The use of nickel to modify the properties of silica-alumina has been extensively studied for the OLI of ethene, [131][132][133][134][135] propene 136,137 and butene. 138,139 In the context of FTS, it is worthwhile pointing out that these catalysts are sensitive to water and deactivation has been reported when NiO/SiO 2 -Al 2 O 3 catalysts adsorb as little as 0.5% moisture.…”

Oligomerisierung von n-Butenen

“…Schon durch Untersuchungen von Hogan et al [25] an NiO-Al 2 O 3 -SiO 2 -Katalysatoren konnte nachgewiesen werden, dass die Reaktivität der Olefine analog der ist, die für homogene Nickelkoordinationsverbindungen gefunden wurde. Grundlegende Untersuchungen an unterschiedlich zusammengesetzten NiOAl 2 O 3 -SiO 2 -Katalysatoren bei der Dimerisierung von Ethen zeigten, dass die Eigenschaften des Katalysators durch das Ni/Al-Verhält-nis bestimmt werden und dass zwei Arten katalytisch aktiver Zentren wirksam sind [26].…”

Polymer synthesis by solid-acid catalyst based on heteropolyacid ammonium salt

“…Polymerization with solid-acid catalysts is gathering much attention due to their significant advantages: (1) facile separation of catalyst from the product is attained by filtration, (2) corrosion of reactor materials can be avoided, (3) no inactivation of catalyst is necessary, and (4) reuse of catalyst is available. Heteropolyacids [6][7][8][9][10], metal oxides [11,12], montmorillonite clay [13,14], and silicate gel of rare earth metals (yttrium, neodymium, and samarium) [15] have been investigated as the solid-acid catalysts for polymer synthesis. Specially, the heteropolyacids with Keggin structure are well known as effective solid-acid catalysts due to its strong Brønsted acid activity and high thermal stability [1][2][3]5].…”