CHAPTER II
REVIEW OF RELATED LITERATURE
This chapter presents the related literature and studies that will be used to
support the development of the bioethanol production machine. This chapter will
focus mainly on bioethanol production machine and as well as the raw material
that will be used in the production of bioethanol.
Conceptual Literature
This part contains data for a thorough understanding of the study by
presenting related topics and useful assumptions from various sources.
I. Bioethanol
A. Description
Bioethanol (also known as grain alcohol, CH3–CH2–OH, or ETOH) is a
liquid biofuel that may be made from a variety of biomass feedstocks using a
variety of conversion processes. Bioethanol is being studied as a possible
replacement for conventional gasoline. It may be used straight in automobiles or
combined with gasoline to reduce greenhouse gas emissions and fuel usage.
Bioethanol is a popular alternative fuel since it is a sustainable bio-based resource
that is oxygenated, which means it can help minimize particle emissions in
compression-ignition engines (Hansen et al., 2005). Bioethanol has a greater
octane number than gasoline, as well as a wider range of flammability limitations,
faster flame speeds, and higher vaporization temperatures. These qualities allow
for a greater compression ratio, a shorter burn period, and a leaner burn engine in
, an internal combustion engine, resulting in potential efficiency improvements over
gasoline (Balat, 2005). The octane number is a measure of gasoline quality that
may be utilized to avoid cylinder knocks by preventing early ignition. In internal
combustion engines, higher octane values are preferable.
According to the study of Carrillo-Nieves et al., (2019) blending bioethanol
with gasoline may not necessitate engine modification, although it may aid to
improve ignition or engine performance. E85 and E10 are the most regularly
utilized mixtures. Bioethanol has a high-octane rating, which improves engine
efficiency and performance and it also has a low boiling point, a wide range of
flammability, a greater compression ratio and heat of vaporization, comparable
energy content, a shorter burn period, and a lean burn engine (Carrillo-Nieves et
al., 2019).
II. Bioethanol Production Process
Pretreatment, hydrolysis, fermentation, and ethanol recovery are all
processes involved in the manufacture of bioethanol from various feedstocks. The
following procedures are described in detail:
A. Pre-Treatment
Pretreatment is divided into four categories including physical, chemical,
physicochemical, and biological pretreatment (Hill et al., 2006). (1) physical
pretreatment, which entails breaking down the size of the lignocellulosic biomass
and crystallinity using methods such as milling, grinding, irradiation, and extrusion;
and (2) chemical pretreatment, which entails the use of chemicals to break down
the size of the lignocellulosic biomass and crystallinity. As a result, the surface
REVIEW OF RELATED LITERATURE
This chapter presents the related literature and studies that will be used to
support the development of the bioethanol production machine. This chapter will
focus mainly on bioethanol production machine and as well as the raw material
that will be used in the production of bioethanol.
Conceptual Literature
This part contains data for a thorough understanding of the study by
presenting related topics and useful assumptions from various sources.
I. Bioethanol
A. Description
Bioethanol (also known as grain alcohol, CH3–CH2–OH, or ETOH) is a
liquid biofuel that may be made from a variety of biomass feedstocks using a
variety of conversion processes. Bioethanol is being studied as a possible
replacement for conventional gasoline. It may be used straight in automobiles or
combined with gasoline to reduce greenhouse gas emissions and fuel usage.
Bioethanol is a popular alternative fuel since it is a sustainable bio-based resource
that is oxygenated, which means it can help minimize particle emissions in
compression-ignition engines (Hansen et al., 2005). Bioethanol has a greater
octane number than gasoline, as well as a wider range of flammability limitations,
faster flame speeds, and higher vaporization temperatures. These qualities allow
for a greater compression ratio, a shorter burn period, and a leaner burn engine in
, an internal combustion engine, resulting in potential efficiency improvements over
gasoline (Balat, 2005). The octane number is a measure of gasoline quality that
may be utilized to avoid cylinder knocks by preventing early ignition. In internal
combustion engines, higher octane values are preferable.
According to the study of Carrillo-Nieves et al., (2019) blending bioethanol
with gasoline may not necessitate engine modification, although it may aid to
improve ignition or engine performance. E85 and E10 are the most regularly
utilized mixtures. Bioethanol has a high-octane rating, which improves engine
efficiency and performance and it also has a low boiling point, a wide range of
flammability, a greater compression ratio and heat of vaporization, comparable
energy content, a shorter burn period, and a lean burn engine (Carrillo-Nieves et
al., 2019).
II. Bioethanol Production Process
Pretreatment, hydrolysis, fermentation, and ethanol recovery are all
processes involved in the manufacture of bioethanol from various feedstocks. The
following procedures are described in detail:
A. Pre-Treatment
Pretreatment is divided into four categories including physical, chemical,
physicochemical, and biological pretreatment (Hill et al., 2006). (1) physical
pretreatment, which entails breaking down the size of the lignocellulosic biomass
and crystallinity using methods such as milling, grinding, irradiation, and extrusion;
and (2) chemical pretreatment, which entails the use of chemicals to break down
the size of the lignocellulosic biomass and crystallinity. As a result, the surface
