These reductions increase as the amount of biodiesel blended into diesel fuel increases. The best emissions reductions are seen with B100.
The use of biodiesel decreases the solid carbon fraction of particulate matter (since the oxygen in biodiesel enables more complete combustion to CO2) and reduces the sulfate fraction (biodiesel contains less than 24 ppm sulfur), while the soluble, or hydrocarbon, fraction stays the same or increases. Therefore, biodiesel works well with new technologies such as diesel oxidation catalysts (which reduce the soluble fraction of diesel particulate but not the solid carbon fraction).
Emissions of nitrogen oxides increase with the concentration of biodiesel in the fuel. Some biodiesel produces more nitrogen oxides than others and some additives have shown promise in modifying the increases. More R&D is needed to resolve this issue.
Biodiesel has physical properties very similar to conventional diesel.
Biodiesel's Physical Characteristics:
Specific gravity |
0.87 to 0.89 |
Kinematic viscosity @ 40°C |
3.7 to 5.8 |
Cetane number |
46 to 70 |
Higher heating value (btu/lb) |
16,928 to 17,996 |
Sulfur, wt% |
0.0 to 0.0024 |
Cloud point °C |
-11 to 16 |
Pour point °C |
-15 to 13 |
Iodine number |
60 to 135 |
Lower heating value (btu/lb) |
15,700 to 16,735 |
BioDiesel is packed in 35 kg carboys, 225 kg MS Barrels and Bulk in Tankers.
Biodiesel is an alternative fuel similar to conventional or "fossil" diesel. Biodiesel meets most of chemical /physical standard of petrodiesel & being plant based, it does not emit Sulphur/CO on burning & are non-toxic, non-polluting, bio-degradable & environment friendly. With no sulphurdioxide emission & unburn hydro-carbons, biodiesel is an ideal fuel for heavily polluted cities. Biodiesel derived from the tree borne oil & fats of plants like Jatropha Curcas, Sunflower, Rapeseeds, Palm, and Karanj etc can be used as a substitute or an additive to petrodiesel. Biodiesel can also be processed from animal fats & used vegetable oils. As an alternative fuel, biodiesel can provide power similar to conventional petrodiesel & this can be used safely in diesel engines without any modification of the currently used diesel engines. Like Mercedes, Daimler Chrysler & other renowned Automobile manufacturers like Mahindra & Mahindra, Tata Motors in India have by now extended the engine warranty on use of biodiesel in their vehicle.
Biodiesel is a clean, renewable and domestically produced diesel fuel, which has many characteristics of a promising alternative energy resource. The most common process for making biodiesel is known as transesterification. This process involves combining any natural oil (vegetable or animal) with virtually any alcohol, and a catalyst. There are other thermochemical processes available for making biodiesel, but transesterification is the most commonly used one due to the simplicity and high energy efficiency. The high energy efficiency of transesterification is an important aspect of Biodiesel, which makes it favorable in the competitive energy market.
The chemistry lies in transforming the Fatty acid chains into Alkyl Esters of respective fatty acids present in different feed oils used and isolation of glycerol present in the Triglyceride molecule in the oils and fats.
Biodiesel fuel can be made from new, used or non-edible vegetable oils, which are non-toxic, biodegradable, renewable resources. Oils are chemically reacted with methanol to produce chemical compounds known as fatty acid methyl esters. Biodiesel is the name given to these esters when they are intended for use as fuel. Glycerol (used in pharmaceuticals and cosmetics, among other markets) is
produced as a co-product.
Biodiesel can be produced by a variety of esterification technologies. The oils are filtered and preprocessed to remove water and contaminants. If free fatty acids are present, they can be removed or transformed into biodiesel using special pretreatment technologies. The pretreated oils are then mixed with methanol and a catalyst (usually potassium hydroxide). The oil molecules (triglycerides) are broken apart and reformed into esters and glycerol, which are then separated from each other and purified.
Approximately 55% of the biodiesel industry can use any oil feedstock, including recycled cooking oils. The other half of the industry is limited to vegetable oils the least expensive of which is jatropha oil. The jatropha oil industry has been the driving force behind biodiesel commercialization in India because of large production capacity, product surpluses, and declining prices. Similar issues apply to the recycled oils industry, even though these feedstock are less expensive than jatropha oils.
