Analysis of the Jatropha seed shows the following chemical
composition :
Moisture 6.20%
Protein 18.00%
Fat 38.00%
Carbohydrates 17.00%
Fiber 15.50 %
Asg 5.30%
The oil conten is 35 - 40 in the see and 50 - 60 % in
the kermel. The oil contains 21% satured fatty acids and 79 % unsaturated fatty acids. There are some chemicals elements in the seed which are poisonous and render the oil not appropriate for
human consumption.
It is significant to point out that, the non-edible vegetable oil
of jatropha curcas has the requisite potential of providing a promising and commercially viable alternative to diesel oil since it has desirable physicochemical and performance
characteristics comparable to diesel. Cars could be run with Jatropha Curcas without requiring much change in design.
The chemical analysis of Jatropha Curcas is given in Table
(1).
ITEM VALUE
Acid
value 38.2
Saponification
value 195.0
Iodine
value 101.7
Viscosity (31°C) "Fatty Acid" 40.4
Palmitic acid
% 4.2
Stearic
acid % 6.9
Oleic
acid % 43.1
Linoleic
acid % 34.3
Other
acids % 1.4
The comparison of properties of Jatropha oil and standard
specifications of diesel oil are shown in Table (2).:
SPECIFICATIONS
STANDARDS SPECS JCO STANDARD SPECS DIESEL
Specific
Gravity
0.9186 0.82
/ 0.84
Flash
point 240/110
°C 50°
C
Carbon
residue
0.64
0.15 or less
Cetane
Value
51.0
50.0 up
Distillation
Point 295
°C
350 °C
Kinematics
viscosity 50.73
CS 2.7
cs up
Sulphur
% 0.13
%
1.2 % or less
Calorific
Value 9 470 kcal /
kg 10 170 kcal / kg
Pour
point
8 °
C
10° C
Colour
4.0
4 or less
Table (3) : Physical and Chemical properties of Diesel Fuel and
Curcas Oil
Table (3)
PROPERTY
CURCAS OIL
DIESEL OIL
Viscosity (cp)
30°C 52.6
(5.51)2
3.60
Specific Gravity 15° /
4° 0.917 /
0.923 0.841 / 0.85
C
(0.881)
Solidifying point
(°C)
2
0.14
Cetane
Value
51.0
(38)
47.8 . 59
Flash point
°C
110 / 340
80
Carbon Rsidue
%
0.64
< 0.05 < 0.15
Distillation
°C
284 . 295 < 350 .
< 370
Sulphur %
0.13 . 0.16
< 10.12
Acid
Value
1.0 . 38.2
Saporification
Value 188 . 198
Iodine
value
90.8 . 112.5
Refractive Index
(30°C) 1.47