Hydroformylation by supported aqueous-phase catalysis: a new class of heterogeneous catalysts

Ligand modified real heterogeneous catalysts for fixed-bed hydroformylation of propylene

“…One is often referred to anchored catalysts [9], tethered catalysts [10], supported aqueous phase (SAP) catalysts [11,12] and supported ionic liquid phase (SILP) catalysts [13,14] as heterogenized homogeneous catalysts; the other is the biphasic system [15] using aqueous biphase [16], supercritical fluids [17][18][19] and ionic liquids [20]. In these works, interesting concepts have emerged, however, they suffer from low selectivity, reactivity (TOF) and recyclability, high metal leaching, or expensive ligands, and hence, need to be improved for practical applications [21].…”

The PPh3 ligand modified Rh/SiO2 catalyst for hydroformylation of olefins

“…Approaches for immobilization of homogeneous complex to solve this problem have been explored, which can broadly be grouped into two types. Firstly, biphasic systems involve in designing the catalyst so that it is soluble in a solvent as a "liquid carrier", under some conditions, is immiscible with the reaction products [9][10][11][12][13]. Another strategy has long been attachment of the catalyst to polymers resin or silica and the separation are recyclable by a simple filtration [14][15][16][17].…”

Multiphasic heterogeneous catalysis mediated by catalyst-philic liquid phases

“…Along with the advantage of immobilization of the organometallic species, SAPC offered high surface area of the support, which translated into a high interfacial area, and the possibility of selectivity variations from bulk equilibrium product distribution through the effect of the interface. 9,10 Among the differences between SAPC and SL-PC: the authors highlighted that while SL-PC is designed for gas-phase reagents SAPC was very efficient for liquid phase reagents. Fig.…”

“…The concept was transferred to batch reactions, using a catalyst dissolved in a supported aqueous phase, and was first referred to as supported aqueous phase catalysis (SAPC) by Davis in a paper published on Nature in 1989. 9 Later, the concept was extended, using a variety of names as we shall see, but the essence has remained the same: a supported catalystphilic phase.…”