Glycerol aqueous phase reforming

Aqueous phase reforming of glycerol in several studies by Dumesic and co-workers has been reported [270, 275, 277, 282, 289, 292, 294, 319]. The first catalysts that they reported were platinum-based materials which operate at relatively moderate temperatures (220-280 °C) and pressures that prevent steam formation. Catalyst performances are stable for a long period. The gas stream contains low levels of CO, while the major reaction intermediates detected in the liquid phase include ethanol, 1,2-pro-panediol, methanol, 1-propanol, propionic acid, acetone, propionaldehyde and lactic acid. Novel tin-promoted Raney nickel catalysts were subsequently developed. The catalytic performance of these non-precious metal catalysts is comparable to that of more costly platinum-based systems for the production of hydrogen from glycerol. 

APR [Aqueous-Phase Reforming] A process for making hydrogen or lower alkanes from carbohydrates, biomass, or glycerol from biodiesel production. The catalyzed process operates at a relatively low temperature (180 to 260°C). Developed from 2001 at the University of Wisconsin and later by Virent Energy Systems, which operated a demonstration plant from 2006. 

A first-order kinetics with respect to glycerol was adopted to describe the catalytic conversion of glycerol to hydrogen by aqueous-phase reforming on Pt/y-alumina catalyst [148]. Extra information about two-bed membrane reactor model is given in Iliuta et al. [148]. 

Cortright R.D. (2006) Hydrogen generation via aqueous-phase reforming of glycerol. Small Fuel Cells Conference, April 2-4, Washington DC, US. 

Keywords glycerol, Pt/NaY, impregnation, hydrogenolysis, aqueous-phase reforming... 

Two-bed membrane reactor for integrated process involving aqueous-phase glycerol reforming to synthesis gas coupled with DME synthesis process combines two physically separated enclosures (Figure 5.13). The first unit is a tube-in-tube fixed-bed water perm-selective membrane reactor for DME synthesis process. The reaction-side compartment (outer tube) is packed with bifunctional catalytic particles for DME synthesis, whereas the permeate-side compartment (inner tube) is an empty... 

Figure 5.13 Schematic diagram of two-bed reactor system for DME production from glycerol via an integrated process involving aqueous-phase glycerol reforming coupled with DME synthesis process.

Figure 5.14 Steady-state axial profiles of the volumetric gas flow rate (a) and temperature (b) for aqueous-phase glycerol reforming and DME synthesis without in situ H2O removal.

With in situ H2O removal, the exothermic reactions in DME synthesis unit make possible the endothermic aqueous-phase glycerol reforming process, and the aqueous-phase glycerol reforming process produces the synthesis gas appropriate for DME synthesis process (Figure 5.15). Simulations surest that allothermal operation could be achieved the overall energy balance is favorable, and the synthesis gas produced in... 

CO = 0.5% Aqueous-phase glycerol reforming unit-trickle-bed reactor ... 

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