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| BIODIESEL AS AUTOMOBILE |
4.0 Biodiesel Specifications
The key components, which determine the quality of biodiesel are monoalyl esters, dialkyl esters, residual vegetable oil, free glycerin, reactant alcohol, free fatty acids and the residual catalyst. In December 2001, American Society of Testing & Materials (ASTM) issued a specification (D6751) for biodiesel (B100) which is presented in Table-6. A provisional specification for B20 biodiesel is also notified by the ASTM known as ASTM PS121 (Table-7). Table-8 summarizes standards for biodiesel in various countries and Table-9 shows a comparison of selected properties of biodiesel and petrodiesel.
Table-6: ASTM Specification (D6751) for B100
| Property |
ASTM Method |
Limits |
Units |
|
Flash Point |
D93 | 130 min. | Degrees C |
| Water & Sediment | D2709 |
0.050 max. | % Volume |
| Kinematic Viscosity (40 C) | D445 |
1.9-6.0 | mm2/sec |
| Sulfated Ash | D874 |
0.020 max. | % mass |
| Sulphur |
D5453 | 0.05 max. | % mass |
| CopperStrip Corrosion | D130 |
No.3 max. | |
| Cetane |
D613 | 47 min. | |
|
Cloud Point |
D2500 | Report |
Degrees C |
|
Carbon Residue (100% Sample) |
D4530* | 0.050 max. | % mass |
| Acid Number |
D664 | 0.80 max. | Mg KOH/gm |
| Free Glycerin |
D6584 | 0.020 max. | % mass |
| Total Glycerin | D6584 |
0.240 max. | % mass |
| Phosphorous Content | D4951 |
0.001 max. | % mass |
| Distillation Temperature (90% Recovered) |
D1160 | 360 max. | Degrees C |
*The carbon residue shall be run out on the 100% sample.
Table-7: ASTM PS121 for B20
| Property |
ASTM Method |
Limits |
Units |
|
Flash Point |
D93 |
100 min. |
Degrees C |
|
Water & Sediment |
D2709 |
0.050 max. |
% Volume |
|
Kinematic Viscosity (40 C) |
D445 |
1.9-6.0 |
mm2/sec |
|
Sulfated Ash |
D874 |
0.020 max. |
% mass |
|
Sulphur |
D5453 |
0.0015 max. |
% mass |
|
Copper Strip Corrosion |
D130 |
No. 3 max. | |
| Cetane Number | D613 |
46 min. | |
| Cloud Point | D2500 |
Report |
Degrees C |
|
Carbon Residue (100% Sample) |
D4530 |
0.050 max. |
% mass |
|
Carbon Residue (Ramsbottom) |
D524 |
0.090 max. |
% mass |
|
Acid Number |
D664 |
0.80 max. |
Mg KOH/gm |
|
Free Glycerin |
D6584 |
0.020 max. |
% mass |
|
Total Glycerin |
D6584 |
0.240 max. |
% mass |
Table-8: Biodiesel Standards of Different Countries
| Specifications |
Units |
Australia |
France |
Germany |
Italy |
Sweden |
USA |
Draft EU |
|
Standard/Specification |
ONC1191 |
- |
DINE51606 |
UNI10635 |
SS155436 |
ASTMD6751 |
EN14214 | |
|
Introduction Date |
Jly 1997 |
Spt1997 |
Spt1997 |
Apr1997 |
Nov1996 |
Dec2001 |
2001 | |
|
Density @15ċ |
g/cm3 |
0.85-0.89 |
0.87-.89 |
.875-0.90 |
0.86-0.90 |
0.87-0.90 |
- |
0.86-0.90 |
|
Viscosity@40ċ |
mm2/s |
3.5-5.0 |
3.5-5.0 |
3.5-5.0 |
3.5-5.0 |
3.5-5.0 |
1.9-6.0 |
3.5-5.0 |
|
Flash Point |
ċ |
≥100 |
≥100 |
≥110 |
≥100 |
≥100 |
≥130 |
≥130 |
|
CFPP |
ċ |
0/-15 |
- |
0-10/-20 |
- |
-5 |
- |
0/-15 |
|
Pour Point |
ċ |
- |
-10 |
- |
0/-15 |
- |
- |
- |
|
Sulphur |
%max |
0.02 |
0.02 |
0.01 |
0.01 |
0.01 |
0.05 |
0.01 |
|
CCR 100%max |
0.05 |
- |
0.05 |
- |
- |
0.05 |
- | |
|
10%disti.residue |
%max |
- |
0.3 |
- |
0.5 |
- |
- |
0.3 |
|
SulphatedAshx |
%max |
0.02 |
- |
0.03 |
- |
- |
0.02 |
0.01 |
|
(Oxid).Ash ,mx |
%mass |
- |
- |
- |
0.01 |
0.01 |
- |
- |
|
Water max. |
mg/kg |
- |
200 |
300 |
700 |
300 |
≤0.05 |
500 |
|
TotalContaminants |
mg/kg |
- |
- |
20 |
- |
20 |
- |
- |
|
Cu Corrosion |
3h/50ċ |
- |
- |
1 |
- |
- |
NO.3 |
1 |
|
Cetane No. |
≥49 |
≥49 |
≥49 |
- |
≥48 |
≥47 |
≤≥49 | |
| Neutral No. |
≤0.8 |
≤0.5 |
≤0.5 |
≤0.5 |
≤0.6 |
≤0.8 |
≤0.02 | |
|
Methanol |
%mass |
≤0.20 |
≤0.01 |
≤0.3 |
≤0.02 |
≤0.02 |
- |
≤0.02 |
|
Ester Content |
%mass |
- |
≥96.5 |
- |
≥98 |
≥98 |
- |
≥96.5 |
|
Monoglyceride |
%mass |
- |
≤0.8 |
≤0.8 |
≤0.8 |
≤0.8 |
- |
≤0.8 |
|
Diglyceride |
%mass |
- |
≤0.2 |
≤0.4 |
≤0.2 |
≤0.1 |
- |
≤0.20 |
|
Triglyceride |
%mass |
- |
≤0.2 |
≤0.4 |
≤0.1 |
≤0.1 |
- |
≤0.03 |
|
Free Glycerol |
%mass |
≤0.02 |
≤0.02 |
≤0.02 |
≤0.05 |
≤0.02 |
≤0.02 |
0.25 |
|
Total Glycerol |
%mass |
0.24 |
0.25 |
0.25 |
- |
- |
0.24 |
≤115 |
|
Iodine No. |
≤120 |
≤115 |
≤115 |
- |
≤125 |
- |
- | |
|
C18:3 & higher acids |
≤15 |
- |
- |
- |
- |
- |
10 | |
|
Phosphorous |
ppm |
≤20 |
≤10 |
≤10 |
≤10 |
≤10 |
≤10 |
10 |
|
Alkaline Matter |
(Na,K) |
- |
≤5 |
≤5 |
≤10 |
≤10 |
- |
≤360 |
|
Distillation 95% |
ċ |
- |
≤360 |
- |
- |
- |
≤360 |
* |
|
IBP min. |
ċ |
- |
- |
- |
- |
- |
* | |
|
Bound Glycerin |
- |
- |
- |
- |
- |
Max 0.8 | ||
|
Oxidation Stability |
Hrs. |
- |
- |
- |
- |
- |
6 min. | |
|
Sediment |
- |
- |
- |
- |
- |
≤0.05 | ||
|
Cloud Point |
- |
- |
- |
- |
* |
- | ||
Table-9: Selected Fuel Properties for Petrodiesel & Biodiesel
| Fuel Property |
Petrodiesel |
Biodiesel |
|
Fuel Standard |
ASTM D975 |
ASTM PS121 |
|
Fuel Composition |
C10-C21 HC |
C12-C22 FAME |
|
Lower Heating Value, Btu/gal |
131,295 |
117,093 |
|
Kin. Viscosity, @40 C |
1.3-4.1 |
1.9-6.0 |
|
Specific Gravity, kg/l @ 60 F |
0.85 |
0.88 |
|
Density, lb/gal @ 15 C |
7.079 |
7.328 |
|
Water, ppm by wt. |
161 |
0.05% max. |
|
Carbon, wt% |
87 |
77 |
|
Hydrogen, wt% |
13 |
12 |
|
Oxygen by dif. Wt% |
0 |
11 |
|
Sulphur, wt% |
0.05 max. |
0.00-0.0024 |
|
Boiling Point, Degrees C |
188-343 |
182-338 |
|
Flash Point, Degrees C |
60-80 |
100-170 |
|
Cloud Point, Degrees C |
-15 to 5 |
-3 to 12 |
|
Pour Point, Degrees C |
-35 to -15 |
-15 to 10 |
|
Cetane Number |
40-55 |
48-65 |
|
Stoichometric Air/Fuel Ratio |
15 |
13.8 |
|
BOCLE Scuff, gm |
3,600 |
>7,000 |
|
HFRR, microns |
685 |
314 |
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