Use conversion and rate to size reactors.
Design equations relate reactor volume, conversion X, rate and feed: batch t=N_A0∫dX/(-r_AV); CSTR V=F_A0X/(-r_A); PFR V=F_A0∫dX/(-r_A). Levenspiel plots (F_A0/-r_A vs X) compare volumes. Add energy balance for non-isothermal operation.
For a first-order reaction a PFR needs V=(v₀/k)ln(1/(1-X)).
Reactor design equations convert the desired conversion and the rate into a volume, which is how the size of a reactor is set.
Use conversion and rate to size reactors.
Reactor design equations convert the desired conversion and the rate into a volume, which is how the size of a reactor is set.
The rate law, the feed flow and the target conversion, along with the temperature and pressure of operation.
It is the reactor volume divided by the volumetric flow rate, which sets how long material stays in the reactor.
Typical applications include calculating the volume of a CSTR for 80 percent conversion of a first order reaction, sizing a PFR for a second order reaction at a set feed rate and choosing the residence time that gives the target product yield.
Study "Plug flow reactors" first (topic 83 of 100 in Materials & Chemical). It covers the groundwork this topic builds on.
Conversion definition. Selectivity and yield. Multiple reactions.
For a first-order reaction a PFR needs V=(v₀/k)ln(1/(1-X)).
The next topic is "Catalysis", which builds directly on this one.
It is classed as Advanced in Materials & Chemical (topic 84 of 100). It is an advanced topic. It assumes you are comfortable with the intermediate topics in Materials & Chemical.
Want to practise? Open the interactive course for quick checks, quizzes, simulations and progress tracking.