Pickering emulsions assisted synthesis of fatty acetal over phenyl sulfonic groups grafted on activated charcoal

Abstract

emulsions assisted synthesis of fatty acetal over phenyl sulfonic groups grafted on activated charcoal.

Catalysis in Pickering emulsions

“…50 Examples of non-aqueous mixtures are also being reported. 23,[51][52][53] Here, the liquids are both the phases comprising the emulsion and the reactants. Xu et al studied an acetalization reaction between dodecyl aldehyde and ethylene glycol in emulsions stabilized with carbon-based acid catalysts.…”

“…Xu et al studied an acetalization reaction between dodecyl aldehyde and ethylene glycol in emulsions stabilized with carbon-based acid catalysts. 51 Similarly, the esterification reaction of glycerol with dodecanol is evaluated in simple and double emulsion systems stabilized with polystyrene-grafted silica nanoparticles bearing sulfonic acid centers. 52 Finally, Yang et al used modified silica particles to stabilize a methanol-in-vegetable oil Pickering emulsion for a transesterification reaction.…”

“…Examples of PIC, other than those in the field of biocatalysis with porous silica, MgO or polymersomes, have also been extensively reported. 20,[51][52][53][69][70][71][72][73][74][75][76][77][78][79][80] In the vast majority of the systems, the catalytic activity is attributed to Pd, which is supported on various surface-active particles such as silica or titania amongst others. 16,20,71,72,75,77,78 In ref.…”

“…37 Mineral acids, such as H 2 SO 4 , H 3 PO 4 and HF, are used as homogenous acid catalysts for several applications despite their corrosive nature and the difficulty in recycling at the end of the chemical process. 51 If used, they require a neutralisation step, which makes the process more polluting and expensive. Therefore, in order to implement more environmentally friendly processes with easier methods for product recovery, these mineral acids must be replaced by solid acids.…”

“…82 Solid particles containing polysulfonic acid groups as catalysts at the particle surface have been reported. 23,[51][52][53]70,73 Yang et al functionalised silica nanoparticles with alkyl chains and polysulfonic acid residues to provide the particles with both surface activity and catalytic properties. 53 The usefulness and effectiveness of emulsions stabilised by such particles as reaction vehicles was evaluated for the catalytic transesterification of vegetable oils using methanol under mild conditions.…”