PRACTICAL 1:

FUEL

Introduction• The first step in refining is the seperation

of petroleum into fractions by fractional distillation in an oil refinery. Each fraction consistes of a mixture of hydrocarbon molecules that boils over a range of temperatures. For example, the kerosene fraction is a mixture that boils between 170 and 250 degrees celcius

Aim

• Petroleum, anti-bumping granules ( porcelain chips ), filter paper, retort stand, thermometer ( -10 -360°C ), distillation flask, Liebig condenser, conical flask, wire gauze, tripod stand, evaporating dish, Bunsen burner.

Materials / Apparatus

• Investigating the fractional distillation of Petroleum

Procedure

• A. Fractional distillation of Petroleum1. The apparatus is set up as shown in Figure 1(b).2. The petroleum is heated in the distillation flask.3. The first fraction of petroleum is collected at 30°C - 80°C. 4. The heating is continued and the distillation is collected in separate conical flasks at different

ranges of temperature at 80°C - 120°C, 120°C – 160 °C and 160°C - 200°C.

Procedure

Figure 1(a)

Procedure

Figure 1(b)

Procedure • B. Characteristics of various fractions

5. The colour is observed of each fraction.

6. The viscosity of the fractions is observed by tilting the conical flask. (Figure 2)

7. For each of the fractions, some of it was poured into evaporating dish and it was heated. The colour of the flame is observed and produced soot. (Figure 3)

8. The observation is recorded.

Procedure

Figure 2

Procedure

Figure 3

Result:

• Fraction Temperatur

RangeColour Viscosity Flammability

Petrol 30 ° C – 80° C Colourless Flows easily (non-

viscous)

Burns easily

Naphta 80 ° C - 120 ° C

Yellowish Slightly viscous

Burn with a little soot

Naphta 120 ° C -160° C

Yellow Viscous Burn with a more smoky

flame

Kerosene 160° C - 200° C

Dark brown Very viscous Burn with a very smoky

flame

Observation

Petrol NaphtaPetrolNaphta

Discussions:1. Discuss the flammability of the fractions of

petroleum.• The higher of the temperature, the

flammability will be decreases.2.Discuss the relationship between the boiling

point of the fractions with the:a) colour of the fractions

– The higher of the temperature, the colour of the fraction wiil be darkness

Discussions:b) viscosity of the fractions• The higher of the temperature, the

viscosity of the fractions will be increase

c) the amount of soot produced by fractions

• The higher of the temperature, the amount of soot produced by fractions will be increases

Discussions:3. Fraction X has a formula of C6H14. Predict its

colour , viscosity and the amount of soot produced by X

Fraction X

Temperature range

80 ° C - 120° C

Colour Yellowish

Viscosity Slightly viscous

The amout of soot

Burn with a little soot

Discussions:4. Write a balanced chemical equation to

represent the combustion of gasoline (C8H18).

– C8H18 + 25/2 O2 8CO2 + 9H2O

5. The incomplete combustion of gasoline results in emission of poisonous gasses such as carbon monoxide and nitric oxide. Write a balanced chemical equation to represent the incomplete combustion of gasoline (C8H18).

• C8H18 + 19/2 O2 + N2 8CO + 2NO + 9H2O

Discussions:6. What is biodiesel? • Biodiesel is a form of diesel fuel

manufactured from vegetable oils, animal fats, or recycled restaurant greases. It is safe, biodegradable, and produces less air pollutants than petroleum-based diesel. Biodiesel can be used in its pure form (B100) or blended with petroleum diesel. Common blends include B2 (2% biodiesel), B5, and B20. B2 and B5 can be used safely in most diesel engines.

Discussions:7. What are the advantages of using biodiesel

compare to petroleum fuel. • Advantages• Domestically produced from non-petroluem,

renewable resources • Can be used in most diesel engines, especially

newer ones • Less air pollutants (other than nitrogen oxides)

and greenhouse gases • Biodegradable • Non-toxic • Safer to handle

Conclusion• Petroleum can be separated into its

fractions by fractional distillation.

• As the boiling point of the fraction increases,

a) The darker the colour it is,

b) The more viscous it is, and

c) The more difficult it is burn with more soot are produced.