Optimization of continuous-flow heterogeneous catalytic oligomerization of 1-butene by design of experiments and response surface methodology

Abstract

Crystalline hybrid catalysts based on molybdenum or tungsten oxide and aliphatic diamines were synthesized via simple, ecofriendly reproducible methodologies, starting from commercially available and relatively inexpensive organic and inorganic precursors, and using water as solvent under mild conditions. The crystal structures of the obtained fine powdered solids were solved ab initio from powder X-ray diffraction data. The type of organic component (1,2-diaminoethane, 1,2-diaminopropane, 1,3-diaminopropane) may play a structure-directing role. On the other hand, different metals (M = Mo, W) may lead to isostructural one-dimensional hybrids of the type MO3(L) with the same bidentate diamine ligand L. The prepared catalysts were investigated for the liquid phase oxidation of saturated and unsaturated hydrocarbons (cis-cyclooctene, cyclooctane), using different types of oxidants (O2, H2O2, tert-butyl hydroperoxide). Differences in catalytic performances associated with distinct structural features were investigated.