of biodiesel, methods of production, as well as metagenomic approaches for biodiesel production.
Keywords Biodiesel · Source of biodiesel · Production methods · Metagenomics ·
Microalgae
5.1 Introduction
Nowadays, fossil fuels were considered as the major energy sources worldwide. The
sources of these fuels were limited on the earth crust and may be finished after a
certain time limit. Due to the limited sources and rising price of petroleum oil, it
became a big challenge to the world to find out an alternative of petroleum oils
(Arbab et al. 2015). Petroleum oil is responsible for some harmful effects like this
fuel generates a large amount of toxic gases which play an important role in global
warming and greenhouse effect (Singh et al. 2020a). Behind these facts, fossil fuels
have shown an important role in the global energy demand (Jayed et al. 2009).
Diesel mainly use in diesel engine for the transportation, electricity generation, etc.
The demand of diesel engine is increasing day by day worldwide. This engine is
more economic and emitted low amount of carbon dioxide (Fattah et al. 2018).
Hence, diesel engine is more appropriate and superior compared to other powergenerating devices (Silitonga et al. 2013). Based on much more advantages of the
diesel, it is very urgent to find out the economic and eco-friendly alternative of
petroleum fuels such as petroleum diesel. The alternative energy sources are considered on the basis of fuel efficiency, renewability, economic nature, as well as
environmental impacts. Biofuels like biodiesel, biogas, biomethanol, and bioethanol
are considered as a renewable energy as these fuels are derived from several
biological materials like plant biomass and agricultural residues (Feng et al. 2011;
Shan et al. 2018; Shi et al. 2016).
Biodiesel is found to be one of the effective energy sources which remains an
attractive sector for research all over world (Zain et al. 2020). It is considered as a
cost-effective and renewable source which is able to fulfill the need of petroleum oils
(Canakci 2007a, b; Szczesna Antczak et al. 2009). According to the advantages of
biodiesel, it can be frequently applied in several diesel engines and therefore shows
the same efficiency like petroleum fuels (Du et al. 2008; Ranganathan et al. 2008).
Biodiesel produces a less amount of pollutants such as hydrocarbons, carbon
monoxide, carbon dioxide, and particulate matter in comparison to petroleum
fuels. Hence, it minimizes environmental pollution and is responsible for lowering
global warming (Sheehan et al. 2000; Yee et al. 2009). An overview of biodiesel
production process is shown in Fig. 5.1.
The quality of biodiesel is provisionally estimated by fatty acid composition
found in the biodiesel. Hence, it varies based on biomass used for production
purpose (Ramos et al. 2009; Knothe 2008). The composition of fatty acid in
biodiesel is generally methyl esters or mono alkyl esters that are originated from
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N. Singh et al.
Keywords Biodiesel · Source of biodiesel · Production methods · Metagenomics ·
Microalgae
5.1 Introduction
Nowadays, fossil fuels were considered as the major energy sources worldwide. The
sources of these fuels were limited on the earth crust and may be finished after a
certain time limit. Due to the limited sources and rising price of petroleum oil, it
became a big challenge to the world to find out an alternative of petroleum oils
(Arbab et al. 2015). Petroleum oil is responsible for some harmful effects like this
fuel generates a large amount of toxic gases which play an important role in global
warming and greenhouse effect (Singh et al. 2020a). Behind these facts, fossil fuels
have shown an important role in the global energy demand (Jayed et al. 2009).
Diesel mainly use in diesel engine for the transportation, electricity generation, etc.
The demand of diesel engine is increasing day by day worldwide. This engine is
more economic and emitted low amount of carbon dioxide (Fattah et al. 2018).
Hence, diesel engine is more appropriate and superior compared to other powergenerating devices (Silitonga et al. 2013). Based on much more advantages of the
diesel, it is very urgent to find out the economic and eco-friendly alternative of
petroleum fuels such as petroleum diesel. The alternative energy sources are considered on the basis of fuel efficiency, renewability, economic nature, as well as
environmental impacts. Biofuels like biodiesel, biogas, biomethanol, and bioethanol
are considered as a renewable energy as these fuels are derived from several
biological materials like plant biomass and agricultural residues (Feng et al. 2011;
Shan et al. 2018; Shi et al. 2016).
Biodiesel is found to be one of the effective energy sources which remains an
attractive sector for research all over world (Zain et al. 2020). It is considered as a
cost-effective and renewable source which is able to fulfill the need of petroleum oils
(Canakci 2007a, b; Szczesna Antczak et al. 2009). According to the advantages of
biodiesel, it can be frequently applied in several diesel engines and therefore shows
the same efficiency like petroleum fuels (Du et al. 2008; Ranganathan et al. 2008).
Biodiesel produces a less amount of pollutants such as hydrocarbons, carbon
monoxide, carbon dioxide, and particulate matter in comparison to petroleum
fuels. Hence, it minimizes environmental pollution and is responsible for lowering
global warming (Sheehan et al. 2000; Yee et al. 2009). An overview of biodiesel
production process is shown in Fig. 5.1.
The quality of biodiesel is provisionally estimated by fatty acid composition
found in the biodiesel. Hence, it varies based on biomass used for production
purpose (Ramos et al. 2009; Knothe 2008). The composition of fatty acid in
biodiesel is generally methyl esters or mono alkyl esters that are originated from
106
N. Singh et al.