🧫 Distillation of Petroleum Products
In short
Determination of fractional composition (distillation curve) of light and middle petroleum distillates at atmospheric pressure in temperature range 0–400°C. The test is performed according to PN-EN ISO 3405:2019; Temperature range: IBP > 0°C, FBP < ~400°C. The procedure comprises 11 steps (about 42 min–1 h 17 min in total); it is used for: Quality control of motor gasoline — fractional composition per PN-EN 228, Quality control of diesel fuel — distillation per PN-EN 590, Testing of jet fuel Jet A-1 — distillation per DEF STAN 91-091.
At a glance
- Standard: PN-EN ISO 3405:2019
- Category: Petrochemistry
- Procedure steps: 11
- Total time of stages: 42 min–1 h 17 min
- Temperature range: IBP > 0°C, FBP < ~400°C
- Sample volume: 100 mL
- Product groups: Group 0: LPG; 1: gasolines; 2: kerosenes; 3: diesel; 4: blends
Overview
Atmospheric distillation is one of the oldest and most important methods for characterizing petroleum products. It allows determination of fuel fractional composition — the distillation curve (temperature vs. percent volume evaporated) provides key information about volatility, chemical composition and fuel behavior under operating conditions.
For motor gasolines, the evaporation temperature at 10% (T₁₀) affects cold start ease, T₅₀ affects warm-up speed and acceleration, and T₉₀ and FBP (final boiling point) affect deposit formation in combustion chamber and lubricating oil dilution. For diesel fuel, distillation temperatures affect ignition quality (cetane index), particulate emissions and low-temperature behavior.
The method involves heating 100 mL sample in a standardized distillation flask at a defined rate. Fuel vapors pass through a tubular condenser, condense and collect in a graduated cylinder. Temperature in flask neck is recorded as a function of collected distillate volume. Key curve points are: IBP (initial boiling point), T₁₀, T₅₀, T₉₀, FBP (final boiling point), recovery and residue.
The standard covers light and middle distillates with IBP above 0°C and FBP below approx. 400°C — gasolines, jet fuels, diesel oils, light fuel oils and naphthas. Manual or automatic apparatus may be used; in case of dispute, manual method is preferred.
Method principle
100 mL sample is measured with graduated cylinder and transferred to a distillation flask of standardized dimensions (125 mL flask with side arm). Flask is heated electrically (1000 W heater with stepless regulation). Vapors pass through tubular condenser maintained at 0–60°C (depending on product group). Distillate collects in graduated cylinder placed in cooling bath. Temperature of thermometer in flask neck is read at moment of evaporation of each 5 or 10% volume. Temperatures are corrected to 101.3 kPa pressure. Results are presented as distillation curve or table.
Applications
- Quality control of motor gasoline — fractional composition per PN-EN 228
- Quality control of diesel fuel — distillation per PN-EN 590
- Testing of jet fuel Jet A-1 — distillation per DEF STAN 91-091
- Calculation of cetane index (ISO 4264) — T₁₀, T₅₀, T₉₀ as input data
- Evaluation of kerosene and light fuel oils
- Monitoring refinery processes — control of fraction cut temperature
- Testing petroleum solvents and paint thinners
Key parameters
| Parameter | Value |
|---|---|
| Temperature range | IBP > 0°C, FBP < ~400°C |
| Sample volume | 100 mL |
| Product groups | Group 0: LPG; 1: gasolines; 2: kerosenes; 3: diesel; 4: blends |
| Repeatability (T₅₀) | ±1.5°C (gasoline), ±2.5°C (diesel) |
| Reproducibility (T₅₀) | ±4.3°C (gasoline), ±5.6°C (diesel) |
| Determination time | 30–60 min |
Standard
- Standard number
- PN-EN ISO 3405:2019
- Title (PL)
- Przetwory naftowe i produkty pokrewne pochodzenia naturalnego lub syntetycznego — Oznaczanie składu frakcyjnego metodą destylacji pod ciśnieniem atmosferycznym
- Title (EN)
- Petroleum and related products from natural or synthetic sources — Determination of distillation characteristics at atmospheric pressure
Step-by-step procedure
-
Product group identification
Determine product group: Group 1 — gasolines (IBP <100°C), Group 2 — kerosenes and Jet A-1, Group 3 — diesel (T₁₀ >150°C), Group 4 — blends. Select appropriate cooling conditions and distillation rate.
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Apparatus preparation
Mount clean distillation flask. Connect condenser with appropriate cooling water flow. Place thermometer in flask neck at proper height. Position graduated cylinder under condenser outlet.
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Sample measurement
Measure 100 mL sample with graduated cylinder at ambient temperature. Record sample temperature. Transfer quantitatively to distillation flask.
-
Distillation start
Turn on heater. Regulate heating power to achieve appropriate distillation rate (first distillate drop should appear in required time: 5–15 min for Group 1).
-
IBP reading
Record thermometer temperature at moment first drop of distillate falls from condenser end (Initial Boiling Point). Correct to 101.3 kPa.
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Distillation curve recording
Record temperature at each 5% or 10% volume recovery. Distillation rate: 4–5 mL/min (Groups 1 and 2) or 4–5 mL/min (Group 3). Record as pairs: volume — temperature.
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FBP and end of distillation reading
Record maximum temperature reached during distillation (FBP — Final Boiling Point). Turn off heater. Wait for last distillate drops.
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Recovery and residue measurement
Read distillate volume in cylinder (recovery). Pour residue from flask into 5 mL graduated cylinder — measure residue volume. Loss = 100 - recovery - residue.
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Barometric correction
Correct all temperatures to 101.3 kPa pressure using formula: ΔT = 0.0009 × (101.3 - p) × (273 + T), where p in kPa, T in °C.
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Distillation curve preparation
Prepare table and graph: temperature (°C) vs. percent volume evaporated (%). State IBP, T₁₀, T₅₀, T₉₀, FBP, recovery, residue, loss.
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Apparatus cleaning
After flask and condenser cooling — rinse with acetone. Dry. Check flask condition (no cracks, carbonization deposits).
Required equipment and apparatus
| Equipment | Example | Indicative price |
|---|---|---|
| Automatic distillation apparatus | Normalab NDI 450, PAC OptiDist, Koehler K45703 | 50 000–120 000 PLN |
| Manual distillation apparatus | Koehler K45000 Front View Distillation | 15 000–35 000 PLN |
| Distillation flask 125 mL | Glass flask per ISO 3405 with side arm | 80–200 PLN/pc |
| Tubular condenser | Metal condenser with regulated cooling water flow | 2 000–5 000 PLN |
| Graduated cylinder 100 mL | Glass cylinder class A with 1 mL graduation | 100–300 PLN |
| Thermometer/temperature sensor | ASTM thermometer or Pt100 sensor with 0.1°C resolution | 500–2 000 PLN |
| Barometer | Digital barometer for result correction | 800–2 500 PLN |
Reagents, media and consumables
| Reagent | CAS | Details |
|---|---|---|
| Distillation CRM (gasoline) | — | Certified reference material with known distillation curve, e.g., Paragon Scientific Gasoline Distillation Standard |
| Distillation CRM (diesel) | — | Certified diesel fuel standard with known distillation curve |
| Acetone (for cleaning) | 67-64-1 | Purity ≥99.5%, for rinsing flask, condenser and cylinder |
| Antifoam agent (optional) | — | Silicone oil, few drops for samples prone to foaming (biodiesel) |
| Boiling stones (optional) | — | Porcelain or carborundum, prevent bumping |
Health and safety (OHS)
- Petroleum fuels — highly flammable, distillation conducted in fume hood
- Hot distillation flask (up to 400°C) — risk of severe burns, heat-resistant gloves
- Fuel vapors — toxic and flammable, exhaust ventilation mandatory
- Risk of bumping — boiling stones, careful heating power regulation
- CO₂ extinguisher within reach
- Safety glasses, flame-retardant coat, gloves mandatory
Frequently asked questions
Which standard describes this test?
The test is performed according to PN-EN ISO 3405:2019 — “Petroleum and related products from natural or synthetic sources — Determination of distillation characteristics at atmospheric pressure”.
How does this method work?
100 mL sample is measured with graduated cylinder and transferred to a distillation flask of standardized dimensions (125 mL flask with side arm). Flask is heated electrically (1000 W heater with stepless regulation).
What is the measuring range and accuracy?
Temperature range: IBP > 0°C, FBP < ~400°C; Sample volume: 100 mL; Product groups: Group 0: LPG; 1: gasolines; 2: kerosenes; 3: diesel; 4: blends; Repeatability (T₅₀): ±1.5°C (gasoline), ±2.5°C (diesel).
How long does the test take?
The times given for the individual stages add up to approximately 42 min–1 h 17 min. The procedure comprises 11 steps.
What equipment is required?
Automatic distillation apparatus, Manual distillation apparatus, Distillation flask 125 mL, Tubular condenser, Graduated cylinder 100 mL, Thermometer/temperature sensor, Barometer. Indicative cost of the core instrument (Automatic distillation apparatus): 50 000–120 000 PLN.
Where is this test used?
Quality control of motor gasoline — fractional composition per PN-EN 228; Quality control of diesel fuel — distillation per PN-EN 590; Testing of jet fuel Jet A-1 — distillation per DEF STAN 91-091; Calculation of cetane index (ISO 4264) — T₁₀, T₅₀, T₉₀ as input data; Evaluation of kerosene and light fuel oils; Monitoring refinery processes — control of fraction cut temperature; Testing petroleum solvents and paint thinners.
What safety precautions apply?
Petroleum fuels — highly flammable, distillation conducted in fume hood; Hot distillation flask (up to 400°C) — risk of severe burns, heat-resistant gloves; Fuel vapors — toxic and flammable, exhaust ventilation mandatory; Risk of bumping — boiling stones, careful heating power regulation; CO₂ extinguisher within reach; Safety glasses, flame-retardant coat, gloves mandatory.
Which laboratory can perform this test?
The test is performed by laboratories accredited to ISO/IEC 17025. On LabCoda you can find them by the standard number PN-EN ISO 3405.