Test Method for Smoke Point of Lamp Kerosene

Test Method for Smoke Point of Lamp Kerosene

Lamp kerosene is a light petroleum product specially used for lighting, mainly produced by fractional distillation or cracking of petroleum. It is a type of kerosene, primarily used as fuel for lighting appliances such as kerosene lamps, gas lamps, and blowtorches. It is also widely used in outdoor stoves, storm lanterns, and other equipment.

With stable flame, high brightness, and low tendency to produce black smoke during combustion, lamp kerosene is still practical in areas with limited electricity supply or emergency situations.

Experimental Purpose

The main purpose of testing the smoke point of lamp kerosene is to evaluate the cleanliness and smokeless performance of the fuel during combustion, so as to determine whether it is suitable for lighting or aviation fuel applications.

Evaluate Combustion Cleanliness：The higher the smoke point, the lower the tendency of the fuel to produce black smoke during combustion, indicating lower aromatic content and more complete, cleaner burning. This is especially important for protecting indoor air quality and reducing carbon deposits on lamp chimneys.

Control Product Quality：Smoke point is one of the key quality indicators for lamp kerosene and jet fuel.

Reflect Chemical Composition Characteristics：The smoke point value is closely related to the hydrocarbon structure in kerosene. It can indirectly reflect the refining degree of raw materials and the level of processing technology.

Ensure Service Performance and Equipment Maintenance：Fuels with low smoke points easily cause wick coking (commonly called “wick blooming”) and blackening of lamp chimneys, reducing lighting efficiency and increasing cleaning frequency. This test helps to select high-quality kerosene suitable for long‑term stable use.

Support Aviation Safety and Engine Carbon Deposit Control：In aviation, smoke point is an important parameter to prevent carbon deposits in engine combustion chambers. Carbon deposits may cause hidden dangers such as local overheating and uneven combustion; therefore, fuels with high smoke points are preferred.

Experimental Apparatus

Sample: Lamp kerosene

Apparatus: SD382 Kerosene Smoke Point Tester, in accordance with ASTM D1322

Experimental Procedures

1.Sample PreparationCondition the sample to 20 ± 5 °C to ensure stable temperature. If the sample is turbid, filter and extract it using a toluenemethanol mixture (1:1). Immerse the wick repeatedly at least 25 times, then dry at 110 °C for 30 minutes to remove impurities.

2.Instrument CalibrationSelect two reference fuels whose smoke points bracket the expected smoke point of the sample. Calculate the correction factor using the formula:f=2(As​/Ad​)+(Bs​/Bd​)​where As​, Bs​ = certified smoke points of reference fuels；Ad​, Bd​ = measured smoke points of reference fuels

3.Testing ProcedureManual Method:Light the smoke point lamp and adjust the wick height until the flame is stable.Slowly raise the wick, observe the flame behavior, and record the maximum height of the smokeless flame (to the nearest 0.1 mm).Repeat the test three times and take the average as the result.

4.Data ProcessingCalculate the smoke point:Smoke Point=L×fwhere L = average of three readings, f = correction factor.Report the result to the nearest 0.5 mm (manual method).

Experimental Results and Analysis

The final smoke point results of the three test samples are:

Sample 1: 28.4 mm

Sample 2: 30.7 mm

Sample 3: 27.0 mm

The smoke points range from 27.0 mm to 30.7 mm.The relative deviation of duplicate determinations for all samples is ≤ ±0.1 mm, which meets the precision requirements of ASTM D132224 and IP 367. The test data are valid.