Distillation and Separation Processes MCQs 2026

Reflux ratio R is defined as

1. Avapor flow only✓
2. Bliquid returned to column divided by distillate product✓
3. Cfeed flow divided by bottoms✓
4. Dreboiler duty only✓

Relative volatility α in binary distillation is

1. Areflux ratio✓
2. Bnumber of trays only✓
3. Cratio of vapor pressure or K-values of components✓
4. Dfeed temperature only✓

Underwood equations help find

1. Aminimum reflux for multicomponent feeds✓
2. Bpipe friction only✓
3. Creactor selectivity only✓
4. Dcrystallizer yield only✓

Packed column uses

1. Aonly rotating disks like centrifuge✓
2. Bstructured or random packing for vapor-liquid contact✓
3. Conly screw conveyor✓
4. Donly electrostatic precipitator✓

Sieve tray allows vapor passage through

1. Aonly packing rings✓
2. Bperforations with liquid on tray deck✓
3. Conly membrane pores in liquid✓
4. Donly external heat exchanger tubes✓

Murphree tray efficiency relates

1. Aactual to theoretical composition change on tray✓
2. Bpump efficiency✓
3. Cturbine isentropic efficiency✓
4. Dfilter cake moisture only✓

q-line (feed line) slope depends on

1. Aonly condenser pressure✓
2. Bonly reboiler type✓
3. Cfeed thermal condition q✓
4. Donly pipe diameter✓

Azeotrope limits separation because

1. Arelative volatility becomes zero or one✓
2. Bpressure is zero✓
3. Ctrays disappear✓
4. Dliquid and vapor compositions equal at that point✓

McCabe-Thiele method uses

1. Aonly pump curves✓
2. Boperating lines and equilibrium curve on x-y diagram✓
3. Conly stress-strain✓
4. Donly Bode plot✓

Minimum reflux gives

1. Azero stages✓
2. Bmaximum distillate always✓
3. Cazeotrope elimination always✓
4. Dinfinite stages for specified separation✓