Catalyst straight-through transport

Estimate the time that a catalyst particle and a gas-phase moiecule spend in the Sasol straight-through transport reatnor (STTR). What is the bulk density of the catalyst (kg cat/m ) in the STTR ... 

A plentitude of different flow field structures have been described in the literature starting from simple arrays of fence posts via arrays of straight parallel chaimels to complex serpentine type stmctures. In addition foam type structures, expanded metals and woven designs have been proposed as well. Under ordinary circumstances, gas flow will be maintained in the channels of the flow field while transport to the reaction site is by diffusion through the porous gas diffusion media next to the catalyst layer. 

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