Direct synthesis of hydrogen peroxide over Au–Pd catalyst in a wall-coated microchannel

Direct synthesis of hydrogen peroxide using concentrated H2 and O2 mixtures in a wall-coated microchannel – kinetic study

“…Our approach was to apply a wash-coated silica layer embedded with Au-Pd colloidal nanoparticles as a catalytic layer for the direct synthesis of hydrogen peroxide inside a wall-coated microchannel [23,24] . We demonstrated that a concentration as high as 5 wt% of hydrogen peroxide can be generated in an acidified aqueous phase using a pure H 2 and O 2 at 1:1 ratio.…”

“…Moreover, these catalytic layers proved to be stable even after several weeks of operation under the given reaction conditions. An increase in reactant concentration in the gas phase or a high(er) reactant partial pressure proved to be highly beneficial for the selectivity [23] . The effect of addition of Au to Pd is often assigned to the dilution of the Pd surface and blockage of O 2 or H 2 O 2 dissociation sites.…”

“…The slurry suspension contains large particles and smaller binder particles (typically two orders of magnitude smaller in size), which act as a "glue" between large particles improving the contact and cohesion. Details on the coating procedure and coating set-up used are given in our earlier publication [23] .…”

Propylene epoxidation with hydrogen peroxide in acidic conditions

“…However, a higher acid concentration is not recommended in the direct synthesis of H 2 O 2 due to possible dissolution of the catalyst (Samanta, 2008). A sulphuric acid concentration of [0.05 M] was shown to be sufficient for the stabilization of hydrogen peroxide (Paunovic et al, 2014;Liu and Lunsford, 2006). The study of sulphuric acid effect on the PO ring opening provides important information for the combination of the in-situ H 2 O 2 synthesis with the propylene epoxidation.…”

Immobilized lipase catalyzed synthesis of n‐amyl acetate: parameter optimization, heterogeneous kinetics, continuous flow operation and reactor modeling

“…37,38 The RSM tool helps in independent parameter optimization and quantifying the effect of parameter interaction on response variables and has been used widely for enzymatic processes. 59,60 In this work, we attempted to coat the reactor wall with immobilized lipase for the production of flavour esters. Batch operations are popular due to their simple design and provision for temperature control and a stirring system to keep biocatalysts in suspension.…”