Biodiesel Production: A Comprehensive Review

This assignment presents a comprehensive review of biodiesel production, encompassing various aspects such as feedstocks (edible & non-edible oils, algae), production processes (esterification & transesterification), catalysts, life cycle assessments, and emission characteristics. The document also highlights the advantages and challenges associated with biodiesel utilization in diesel engines. It explores recent research trends and advancements in this field, providing valuable insights into the future of biodiesel as a sustainable fuel alternative.

Running head: BIODIESEL
Biodiesel
Name of the student:
Name of the university:
Author note

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Introduction
Biodiesel is an alternative to fuel which can be considered similar to the conventional or
fossil diesel. It is produced directly from vegetable oil, animal fats, tallow and the waste of
cooking oil. The method by which these products are used for transforming into the form of
biodiesel is known as transesterification. The major sources of oil are the rapeseed, palm and
soybean. Most of the biodiesel produced in UK comes from the rapeseed. But the contemporary
production of biodiesel is sourced from the wasted vegetable oils of restaurants, chip shops,
industrial food producers and so on (Gui, Lee and Bhatia 2008). As the raw oil is very costly
therefore the oil directly from the agricultural industry is not produced for the commercial
purpose even though it can be considered as the greatest possible source. The final cost of the oil
after the addition of transforming it to biodiesel is a lot as compared to fossil fuel Although
waste vegetable oil can be available for free or at a very cheap rate but it needs to purified before
converting to biodiesel. The fact is that the biodiesel that is produced from the waste of vegetable
oil has the ability to compete with fossil diesel. This assignment will look into the benefits of
biodiesel and the different factors that play an important role in its production.
Benefits of biodiesel
Biodiesel is an environmental friendly product which has many beneficial properties. One
of the important benefits of biodiesel is that it can be considered carbon neutral. The specific
term refers to the fact there is no net output of carbon from this fuel in the form of carbon
dioxide. The reason behind this effect is that same amount of carbon dioxide is absorbed as well
as released in the process of growing of the crop and the combustion of the fuel (Balat 2011).
Moreover, the carbon dioxide is released in the production of the fertilizer which is necessary to
fertilize the agricultural field in which the oil crops are cultivated. Biodiesel is a biodegradable

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product which is totally non- toxic that is, spillage of the fuel pose a minimum amount of risk as
compared to the spilling of fossil diesel. It also has a higher flashpoint as compared to fossil
diesel and therefore safe and secured in the course of crash (Atabani et al. 2013).
Production of biodiesel
Fig: Production Flowchart
Source: (Avinash, Subramaniam and Murugesan 2014)
In the production of biodiesel, the process of transesterification is used which is also
known as alcoholysis. It involves the displacement of alcohol from an ester by another alcohol in
a process which is similar to the method of hydrolysis with a slight difference of using water in
the other. Non- edible plant oils are also used for crude oil production of biodiesel. When the use

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of non- edible oils are compared to edible oils, it is found to be significant as well as costly but
there is availability at large. The production of biodiesel from the non- edible oilseed crops
includes jatropha, karanja, tobacco and so on (Churchill and Srinivasan 2017).
The production of biodiesel from the waste cooking oil into the partial alternative of
petroleum diesel is a probable option for solving the issues of energy crisis as well as
environmental pollution. The edible vegetable oil fuels were not taken into consideration because
of their cost which was higher compared to petroleum fuels. The reaction between oil or fat and
alcohol is a process of reversible reaction therefore it must be added in surplus for driving the
reaction in the appropriate direction to enable complete conversion (Collet et al. 2014).
With the success of the transesterification process, the separation of the ester and glycerol
layers are signified after the time of reaction. The production of biodiesel is a complex process
which involves the mixing of alcohol and catalyst followed by the separation and removal of
alcohol. Then the process of glycerin neutralization takes place followed by methyl ester wash. It
must be assured that the finished biodiesel is analyzed by means of sophisticated analytical
equipment so that the necessary specifications are met with (Issariyakul and Dalai 2014). To list
the most crucial factors in the production of biodiesel are- complete reaction, removal of
glycerin, catalyst and alcohol and absence of free fatty acids.

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Fig: Chemical process for methyl ester biodiesel
Source: (Balat and Balat 2008)
Impact of biodiesel
Due to the instability in the political condition of the Organization of Petroleum
Exporting Countries or OPEC the price of fossil fuels ate soaring high. Again the countries with
comparatively lesser production of fuel or without fossil fuel production would be profitable
from the utilization of the previous land resources used for the cultivation of bio- fuel crops. This
is the reason behind the increase in production of bio- fuel each year and there is an assumption
that in the upcoming days, biodiesel is going to be the main bio- fuel all over the world. The
graph of biodiesel production has not fallen down since 1991 (Lee et al. 2014). While studying
the impact of biodiesel in the world, it was found out that the space available in the UK for
producing the biodiesel crops is not enough according to the target set for meeting the renewable
energy production in UK. Also, the demand for water is much more in the bio- fuel crops as
compared to the traditional crops. The second generation bio- fuels also pose certain benefits
such as improving the soil quality, carbon requisition in soil and soil erosion (Murugesan et al.
2009). It was also found out that as the bio- fuel industry has expanded, the price of foods has
increased and there is shortage of land available for the cultivation of food- based crops in most
of the countries of Asia, Africa and Latin America (Rawat et al. 2013).
Advantages of bio- diesel
It is a non- toxic fuel which degrades at a speed four- times faster than diesel whereas
pure bio diesel degrades around 85%- 88% in water. One of the most important advantages of
using biodiesel is that when it I mixed with diesel fuel, the efficiency of engine is increased. The

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storage becomes safe due to the higher flashpoint in bio diesel. Being an oxygenated fuel, it is
implied that the oxygen content plays an important role in making the fatty compounds fit for
diesel fuel by burning the cleaner. Ames mutageniety tests have found out that it is responsible
for reducing the risk of cancer by 90%, thus providing a domestic and renewable supply of
energy (Murugesan et al. 2009). The list of benefits of biodiesel also includes the non-
production of greenhouse effects as the amount of carbon dioxide released in the production
process equals the amount of carbon dioxide used in the plants. It can also be used directly in the
compression of ignition engines without any kind of considerable adjustment in the engine. It
does not contain sulphur and the features are relatable to the future policies of Europe which will
put restriction on the use of sulphur (Singhasuwan et al. 2015). The chemical characteristics of
bio diesel showed that there are lower levels of poisonous and reactive hydrocarbon species
when the bio diesel fuels were used. Along with all these advantages, the bio diesel is not free of
disadvantages which are listed below.
Disadvantages of bio diesel
There are only few disadvantages of biodiesel as compared to its advantages. The use of
bio diesel has resulted in a bit of decrease in the fuel economy on the energy basics. As its
density is more than diesel fuel in the cold weather therefore there might be a need to use the
blends in the sub- freezing conditions. With the decrease in production of vegetable oil it has
become more expensive (Talebian-Kiakalaieh, Amin and Mazaheri 2013).
Bio diesel market development
The market of bio diesel is one of the fastest growing in the chemical industry. The
production of bio diesel is the highest in the European Union where the rate is higher than

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ethanol but the production of both these fuels are comparatively smaller than that of Brazil and
the United States. There are two factors that have made EU the leader in the production of bio
diesel. One factor being the amendment in the Common Agricultural Policy which is a
supranational and locally oriented policy of the farm for the member of European Union
countries. the other factor being the high tax of the fuel which have led to the indirect subsidy of
the production of bio fuel either through full or partial exclusion from the fuel excise tax. In the
EU member countries tax generally comprise 50% or more than the selling price of diesel
(Unosson et al. 2014).
EU is the global leader in the production and consumption of bio diesel with a figure of
4.98 million tones with an increase of 1.8 million in one year. Bio diesel was accountable for
around 80% of the bio fuel production in the EU countries. The EU still continues to be the
leader in the market of bio diesel production and will continue to do so, followed by US and
Brazil. Other countries in the run for bio diesel production include Netherlands, China, India,
Thailand and New Zealand.
Challenges faced
In today’s world biodiesel has to overcome a lot of challenges for becoming the
mainstream energy source. The challenges might be the cost of feedstock, availability of
feedstock, quality of fuel or the changing norms of International Compatibility of Bio diesel
Testing Standards. Such issues are not to be solved in a short span of time which reflects that the
road to achieve biodiesel as the main source of energy is not going to be smooth. It might take a
minimum of 5- 10 years for the change to take place. Bio fuels do not only face technical

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challenges but also come across social, economic and environmental challenges ((Rawat et al.
2013).
A combination of the price hike, shortage of supply and issues related to global climate
change are urging the development of alternative ways apart from the burning of fossil fuels so
that the transportation energy requirements could be met. The best option in this regard can be
considered as the use of liquid fuels that is derived from the cellulosic biomass. These new bio
fuels have the ability of clean burning, carbon- neutral and also renewable. The main focus is on
the technological challenges to produce superior quality of bio fuels in such a way that can win
over sustainability and have economically competitive advantage over gasoline. The other
challenges include the restraint that is posed by market and economics, limitations of resources,
risks related to health, climate forcing, demand of water and land use. To cope up with these
challenges there is a requirement of efficient life- cycle perspective. There is a need to
understand the farmers, feedstock options and predict bio fuel production technologies and
practices for evaluating the transitions and confront with uncertainty (Singhasuwan et al. 2015).
Conclusion
Therefore it can be concluded from this assignment that biodiesel is a renewable fuel that
can be used in place of the diesel fuel manufactured from petroleum. The major sources of
biodiesel include rapeseed oil, sunflower oil and palm oil. The process of bio diesel production is
a complex one involving a number of stages. They are used in regular diesel engines without any
kind of changes in the engine. It can be stored as well as transported with the use of diesel fuel
tanks and other equipments.

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This renewable and clean burning diesel replacement has decreased the dependence on
foreign petroleum to a great deal. The components of production include a diverse mix of feed
stocks which include recycled cooking oil, soya oil and animal fats. Bio diesel is the first and
only EPA- designated advanced bio fuel in the commercial sector of the production process
across the country and also the pioneer in reaching the production level of one billion gallon.
Thus, it can be recommended that it can be used in the diesel engines without any change and
abiding by the stern technical fuel quality and the specifications of engine performance.

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