Summary: Extraction
Summary: Extraction
New knowledge Triangle phase equilibrium diagram cross flow process mass balance in triangle diagram
New knowledge • Triangle phase equilibrium diagram • cross flow process • mass balance in triangle diagram
old method theoretical stage model differential contact model minimum solvent/feed ratio engineering considerations Exercise 1 of week 9 Exercise of this week
Old method • theoretical stage model • differential contact model • minimum solvent/feed ratio • engineering considerations – Exercise 1 of week 9 – Exercise of this week
When to use extraction? Distillation is preferential When distillation is dificult(azeotropic or relative volatility is close to 1) When distillation is inefficient(eg 1% HAc water) When the component is heat sensitive(eg bioproduct, penicillin
When to use extraction? • Distillation is preferential. • When distillation is difficult (azeotropic or relative volatility is close to 1) • When distillation is inefficient (eg 1% HAc water) • When the component is heat sensitive (eg bioproduct, penicillin)
Limitation of extraction AB should be miscible B and s should be immiscible or partially miscible Solvent should be regenerated either through distillation or other methods
Limitation of extraction • AB should be miscible; • B and S should be immiscible or partially miscible; • Solvent should be regenerated either through distillation or other methods
Apparatus for extraction Performance of commercial extraction equipment type Liquid plate spacing between typical capacit /ft plates plications combined or stages streams efficiency ft 3 /ft2-h mixer-settler 75-100 Duo-Sol process spray50-25010-20 ammonia column extraction of salt from caustic soda packed 20-150 phenol column recovery perforated 10-200 1-20 6-24 30-70 furfural p column process agitated 50-100 1-2 80-100 12-24 pharmaceutica tower Is and organic chemicals
Apparatus for extraction • Performance of commercial extraction equipment type Liquid capacity combined streams, ft3/ft2-h HTU /ft plate or stage efficiency (%) spacing between plates or stages, in. typical applications mixer-settler 75-100 Duo-Sol lube-oil process spray column 50-250 10-20 ammonia extraction of salt from caustic soda packed column 20-150 5-20 phenol recovery perforated -plate column 10-200 1-20 6-24 30-70 furfural lube-oil process agitated tower 50-100 1-2 80-100 12-24 pharmaceutica ls and organic chemicals
Leaching When ab is a solid mixture Solid extraction or leaching
Leaching • When AB is a solid mixture • Solid extraction or leaching
Equilibrium is different from quid extraction How? Without chemical reaction With chemical reaction
Equilibrium is different from liquid extraction • How? • Without chemical reaction • With chemical reaction
Equipment is different from quid extraction How and why stationary solid beds moving-bed leaching dispersed solid leaching
Equipment is different from liquid extraction • How and why? • stationary solid beds • moving-bed leaching • dispersed solid leaching
stationary solid beds similar to the cleaning of filtration cake
stationary solid beds • similar to the cleaning of filtration cake
