The WHSV is defined in terms of the propylene feed rate (C3
= WHSV).
This is defined as the mass flow of propylene through the reactor on an hourly basis
divided by the mass of catalyst.
If the space velocity is low (flow through the reactor
is low), there is an increase in the number of side reactions, resulting in decreased
selectivity.
More nPB is generally formed at reduced WHSV at a given temperature.
Typically, the WSHV is 0.7 hr-1 for QZ-2500H.
Previous catalysts generally operated at lower space velocities due to the larger catalyst life zone.