10-Tray Oldershaw Sieve Column with Vacuum Silvered Jacket
Provides 10 visual sieve trays with downcomers inside vacuum-jacketed adiabatic glass column.
Chemical & Process Engineering / Fractional Distillation Column
FREE TO EXPLORELABORATORY 17 · CHEMICAL & PROCESS ENGINEERING
Fractional Distillation Column Reflux Ratio & McCabe–Thiele Tray Efficiency
Operate a continuous sieve-tray distillation column separating an ethanol–water mixture across variable external reflux ratios R, determine distillate purity x_D, and calculate overall Murphree plate efficiency via McCabe–Thiele graphical construction. Explore interactive transport phenomena, unit operations simulation, and chemical engineering telemetry.
TRANSPORT PHENOMENA · UNIT OPERATIONS · PROCESS CONTROL · REACTION ENGINEERING
Your virtual chemical and process engineering laboratory.
DISTILLATE ENRICHMENT FACTOR 1/(1 - X_D)—
PROCESS & PILOT PLANT TELEMETRY
Ready to sample with Reflux R = 3.0 ratio.
Adjust Reflux R, then execute chemical process trial.
Chemical and process engineering telemetry is evaluated rigorously using 64-bit IEEE 754 precision. Residuals reflect ordinary least-squares regression across successive observations. Continuous data structures support high-fidelity transport phenomena and unit operations modeling.
Process engineering assumptions and boundary condition limits
The transport and thermodynamic models apply within the specified calibrated operating window (1.0 to 6.0 ratio). Evaluated using a 10-tray Oldershaw sieve column (internal diameter 50 mm, tray spacing 50 mm) separating a 15.0 mol% ethanol-water feed at atmospheric pressure. Linear regression models 1/(1 - x_D) versus reflux ratio R to extract slope S = 2.8500.
Process apparatus & industrial sensors.
Thermostatically Controlled Reboiler Mantle
1.5 kW electric heating mantle boiling bottoms liquid with internal quartz temperature sensor.
Solenoid-Actuated Dividing Reflux Head
Automated magnetic liquid dividing funnel providing digital reflux ratio control from 0.5 to total reflux.
Shell-and-Tube Overhead Total Condenser
Condenses 100% of overhead vapor at 15.0 °C to provide subcooled liquid reflux and distillate product.
Precision Digital Density Meter (Oscillating U-Tube)
Measures sample density at 20.000 °C to determine ethanol mole fraction with 0.0001 resolution.
Thermocouple Array at Reboiler, Feed, and Overhead
Continuously logs column thermal profile (T_reb, T_feed, T_top) with 0.05 °C accuracy.
FOLLOW THE METHOD
A reason behind every step.
Operate a continuous sieve-tray distillation column separating an ethanol–water mixture across variable external reflux ratios R, determine distillate purity x_D, and calculate overall Murphree plate efficiency via McCabe–Thiele graphical construction. Standardized parameter settings: 1.0, 2.0, 3.0, 4.0, 5.0, 6.0 ratio.
01
Feed Preparation & Column Priming
Charge the reboiler with 2.0 L of 15.0 mol% (30.8 wt%) ethanol-water mixture; turn on cooling water to the overhead condenser at 5.0 L/min.
02
Total Reflux Boil-Up Equilibration
Energize reboiler at 800 W and operate under total reflux (R = ∞) for 30 minutes until all 10 trays are actively bubbling and temperatures stabilize.
03
Initial Reflux Ratio Setting
Set the magnetic reflux timer to R = 1.0 (5 s reflux, 5 s distillate withdrawal); maintain steady reboiler heat duty.
04
Distillate & Bottoms Sampling
Allow 20 minutes to reach compositional steady state; draw 5 mL samples of overhead distillate and bottoms liquor through septum ports.
05
Reflux Ratio Progression Protocol
Step reflux ratio through 2.0, 3.0, 4.0, 5.0, and 6.0, allowing 20 minutes of steady-state equilibration before sampling at each plateau.
06
McCabe–Thiele & Tray Efficiency Analysis
Measure sample ethanol mole fractions x_D and x_B using the density meter, plot 1/(1 - x_D) versus R to extract slope S, and construct McCabe–Thiele stage steps.
YOUR NOTEBOOK · 0 OBSERVATIONS
Turn measurements into chemical process engineering insight.
Points are your recorded observations. The solid regression line validates Fractional Distillation Column mathematical scaling.
LINEAR REGRESSION FIT · y = mx + b
1/(1 - x_D) = S · R + c_0 = 2.8500 · R + 1.2500
| # | External Reflux Ratio R (ratio) | Distillate Enrichment Factor 1/(1 - x_D) (ratio) | External reflux ratio R (L/D) | Distillate enrichment factor 1/(1 - x_D) | Remove |
|---|
No readings yet. Execute a process trial and record it.
Calculate it yourself.
CHECK YOUR UNDERSTANDING
Explain what the process engineering metrics mean.
At total reflux (R = ∞), the rectifying operating line on a McCabe–Thiele diagram:
The ethanol–water system at atmospheric pressure forms a minimum-boiling azeotrope at approximately:
If a distillation column experiences severe weeping on its sieve trays, the Murphree tray efficiency will:
The Fenske equation is used in distillation column design to calculate:
THEORY AND UNIT OPERATIONS CONTEXT
Process engineering background & physical principles.
Fractional distillation is the most widely deployed thermal separation process in the chemical, petrochemical, and pharmaceutical industries, responsible for purifying petroleum fractions, petrochemical intermediates, and alcoholic spirits. In a staged tray column, liquid flows downward across horizontal perforated trays while vapor bubbles upward through perforations or bubble caps, facilitating intimate vapor-liquid mass transfer. On each tray, the more volatile component (ethanol) preferentially vaporizes into the ascending vapor stream, while the less volatile component (water) condenses into the descending liquid stream. Warren L. McCabe and Ernest W. Thiele (1925) formulated the seminal graphical method for determining the theoretical number of equilibrium stages required for a specified separation. Crucially, column performance is governed by the external reflux ratio R = L / D (liquid returned to the column divided by overhead distillate product withdrawn). Increasing the reflux ratio steepens the rectifying operating line (slope = R / (R + 1)), expanding the driving force between the operating line and the vapor-liquid equilibrium (VLE) curve. Consequently, distillate overhead purity x_D increases systematically toward the ethanol-water azeotrope (89.4 mol% ethanol at 1 atm), causing the enrichment factor 1 / (1 - x_D) to scale linearly with reflux ratio R. In this laboratory investigation, an instrumented 10-sieve-tray glass distillation column is operated across reflux ratios from 1.0 to 6.0 to evaluate distillate enrichment slope S and calculate overall Murphree tray efficiency.
1/(1 - x_D) = S · R + c_0 = 2.8500 · R + 1.2500
Evaluated using a 10-tray Oldershaw sieve column (internal diameter 50 mm, tray spacing 50 mm) separating a 15.0 mol% ethanol-water feed at atmospheric pressure. Linear regression models 1/(1 - x_D) versus reflux ratio R to extract slope S = 2.8500.