TABLE
OF CONTENTS
CHAPTER ONE
INTRODUCTION
1.0 GENERAL
INTRODUCTION
1.1 BACKGROUND OF THE STUDY
1.2 ADVANTAGES OF THE USE OF BIODIESEL
1.2.1
EMISSION REDUCTION
WITH BIODIESEL
1.2.2
LOW HYDROCARBON
EMISSION
1.2.3
SMOKE AND SOOT
REDUCTION
1.2.4 POSITIVE ENERGY BALANCE FOR SOLAR ENERGY IN BIODIESEL
1.3 DRAWBACKS
OF THE USE OF BIODIESEL
1.3.1
GELLING
1.3.2
CONTAMINATION
BY WATER
1.3.3 PERFORMANCE
AND MAINTENANCE PROBLEM OF BIODIESEL ENGINE
1.4 HEALTH EFFECT OF BIODIESEL PRODUCTION
1.5 ENVIRONMENTAL CONCERN OF BIODIESEL
PRODUCTION
1.6
TRANSESTERIFICATION OF BIODIESEL
1.7 PROPERTIES OF BIODIESEL
1.7.1 SPECIFIC GRAVITY
1.7.2 KINEMATIC VISCOSITY
1.7.3 WATER AND SEDIMENT
1.7.4 FLASH POINT
1.7.5 CLOUD POINT / POUR POINT
1.7.6 CETANE NUMBER
1.7.7 CALORIFIC VALUE
1.7.8 SULPHUR CONTENT
1.7.9 CARBON RESIDUE
1.7.10 DIESEL INDEX
1.7.11 COPPER STRIP CORROSION
1.8 USES OF BIODIESEL
1.9 PALM
KERNEL OIL AS BIODIESEL
1.10 AIMS OF THE STUDY
1.11 OBJECTIVES OF THE STUDY
1.12 PURPOSE OF THE STUDY
1.13 SCOPE OF THE STUDY
CHAPTER TWO
MATERIALS AND METHODS
2.1 MATERIALS
2.2 REAGENTS
2.3 METHOD
2.3.1 FEEDSTOCK
PRETREATMENT
2.3.2 MIXING
2.3.3 SEPARTION
2.3.4 PRODUCT PURIFICATION/DRYING
CHAPTER THREE
RESULTS,
DISCUSSION, CONCLUSION AND RECOMMENDATION
3.1 EXPERIMENTAL RESULTS
3.2 DISCUSSION OF RESULT
3.2.1 SPECIFIC
GRAVITY
3.2.2
KINEMATIC VISCOSITY
3.2.3 WATER
AND SEDIMENT
3.2.4 FLASH
POINT
3.2.5 POUR
POINT
3.2.6 VACUUM
DISTILLATION
3.2.7 TOTAL
ACID NUMBER
3.3 CONCLUSION
3.4 RECOMMENDATION
REFERENCES
CHAPTER
ONE
INTRODUCTION
1.0 GENERAL INTRODUCTION
Energy is a fundamental pillar of modern society as
well as being an essential building block for socio-economic development
(UNIDO, 2007). The awareness of the imminent depletion of fossil fuels coupled
with a global energy crisis has stimulated interest in the research for
alternative energy source (Garba et al., 1996). The urgent need for alternative
and cheaper energy supplies in Nigeria is increasingly apparent now considering
the epileptic supply and distribution of the fossil fuels that have risen beyond
the reach of Nigerian rural people (Eze, 2003).
The uses of renewable raw materials significantly
contribute to sustainable development usually interpreted as “acting
responsibly to meet the needs of the present without compromising the ability
of future generations to meet their own needs” (Meier, et al., 2007).
Currently, plant oils are the most important renewable
raw materials for the chemical industry. They are triglycerides (tri – esters
of glycerol with long chain fatty acid) (see Fig. 1) with varying composition
of fatty acids depending on the plant, the crop, the season and the growing
conditions.
Figure 1.1: Chemical structure of triglyceride, R =
alkyl groups.
The Table below shows the composition of some oils
that have been used for transesterification to yield biodiesel. It shows the
composition of the fatty acid contained, chain length in carbon atoms and
number of double bonds.
Table 1.1: The
composition of some oils from plant
R(x,y)
=
|
10:0
|
12:0
|
14:0
|
16:0
|
18:0
|
18:1
|
18:2
|
18:3
|
20:0
|
New
rapeseed
|
-
|
-
|
0.5
|
4
|
1
|
60
|
20
|
9
|
2
|
Sun
flower
|
-
|
-
|
-
|
6
|
4
|
28
|
61
|
-
|
-
|
Palm
kernel
|
5
|
50
|
15
|
7
|
2
|
15
|
1
|
-
|
-
|
Linseed
|
-
|
-
|
-
|
10
|
5
|
22
|
15
|
52
|
-
|
Soybean
|
-
|
-
|
-
|
10
|
5
|
21
|
53
|
8
|
0.5
|
R(x,y)
= Composition of the fatty acids;
x = Chain length in carbon atoms;
y = Number of double bonds
Biofuels are a wide range of fuels which are derived
from biomass and can be used as a large source of energy supply. The term
covers solid biomass, liquid fuels and various biogases (Dembras, 2009).
Biofuels are gaining increased public and scientific attention, driven by
factors such as oil price spikes, the need for increased energy security,
concern over greenhouse gas emissions from fossil fuels, and government
subsidies.
Biofuels are drawing increasing attention worldwide as
substitutes for petroleum – derived transportation fuels to help address energy
cost, energy security and global warming concern associated with liquid fossil
fuels. Biofuels include ethanol made from sugar cane or diesel-like fuel made
from soybean oil, dimethyl ether (DME) or Fischer – Tropsch Liquids (FTL) made
from lignocellusosic biomass.
The Energy Commission of Nigeria envisions that in the
short term (2005 – 2007), crude oil will continue to play a dominant role in
the economic development of the country, while in the medium term (2008 –
2015), a transition in energy from crude oil to less carbon – intensive economy
increasingly powered by gas. Also, in the long term (2016 – 2025), the nation’s
energy requirement will be completely non fossil. (ECN, 2005).
A relatively recently popularized classification for
liquid biofuels includes first generation and second generation fuels. There is
no strict technical definitions for these terms but the main distinction
between them is the feedstock used.
First generation fuels are generally those made from
sugar, grains or seeds, i.e. one that uses only a specific (often edible)
portion of the above – ground biomass produced by a plant , and relatively
simple processing is required to produce a finished fuel. First generation
fuels are already being produced in significant commercial quantities in a
number of countries. Members of this group are bioalcohol, biodiesel, green
diesel (also known as renewable diesel), bioether, biogas e.t.c.
Second generation fuels are generally those made from
non-edible lignocellosic biomass, either non-edible residues of food crop production (e.g. corn stalks or
rice husks) or non-edible whole plant biomass (e.g. grasses or trees grown
specifically for energy). Second generation biofuels are basically produced
from sustainable feedstock. Sustainability of a feedstock is defined among
others by availability of the feedstock, impact on greenhouse gas emissions and
impact on biodiversity and land use. Many second generation biofuels are under
development such as cellusoic ethanol, algae fuel, biohydrogen, biomethanol,
Fischer – Tropsch diesel, mixed alcohols, biohydrogen diesel and wood diesel.
1.1 BACKGROUND
OF THE STUDY
Biodiesel (fatty acid methyl esters) is an alternative
fuel for diesel engines. It is an alcohol ester product from the
transesterification of triglycerides in vegetable oils or animals accomplished
by reacting lower alcohols such as methanol or ethanol with triglycerides.
The National Biodiesel Board (USA) technically defined
biodiesel as a mono-alkyl ester. Blends of biodiesel and conventional
hydrocarbon based diesel are products most commonly distributed for use in the
retail diesel fuel market place. Biodiesel contain no petroleum, but it can be
blended at any level with petroleum diesel to create a biodiesel blend. Much of
the world uses a system known as the “B” factor to state the amount of
biodiesel in any fuel mix:
Ø
100%
biodiesel is referred to as B100.
Ø
20%
biodiesel, 80% petrodiesel is labelled B20.
Ø
5%
biodiesel, 95% petrodiesel is labelled B5.
Ø
2%
biodiesel, 98% petrodiesel is labelled B2.
Blends of less than 20% biodiesel can be used in
diesel equipment with no, or only minor modifications. Biodiesel can also be
used in its pure form (B100), but may be blended with petroleum diesel at any
concentration in most injection pump diesel engine. New extreme high-pressure
(29000 psi) common rail engine have strict factory limits of B5 or B20
depending on manufacturers.
Biodiesel has different solvent properties than
petrodiesel, and will degrade natural rubber gaskets and hoses in vehicles
(mostly vehicles manufactured before 1992), although these tend to wear out
naturally and most likely will have already been replaced with FKM, which is
non reactive to biodiesel.
The first diesel engine was produced by Rudolf in
Augsburg and Germany. In remembrance of this event, August 10 has been declared
“International Biodiesel Day”. Rudolf diesel demonstrated a diesel running on
pea nut (at the request of the French government) but for the French otto
company at the world fair in Paris, France in 1990. (Knothe, 2001).
Biodiesel has been known to breakdown deposits of
residue in the fuel lines where petrodiesel has been used. As a result, fuel
filters may become clogged with particulates of a quick transition to pure
biodiesel is made. Therefore, it is recommended to change the fuel filters on
engine and heaters shortly after switching to a biodiesel blend.
Biodiesel is light to dark yellow liquid immiscible
with water, with high boiling point and low vapour pressure. It has been used
as a substitute for diesel fuel in the automobile industry and also referred to
as a diesel – equivalent processed fuel derived from vegetable oils.
(Biodiesel, 2007).
Several research have been performed on the production
of biodiesel and some basic feedstock for the fuel includes animal fats,
vegetable oils, soy, rapseed, jatropha, mahua, mustard, flax, sunflower, palm
oil, hemp, field pennycress, pongamiapinnata and algae. Pure biodiesel is the
lowest emission diesel fuel. Although liquefied petroleum gas and hydrogen have
cleaner combustion, they are used to fuel much less efficient petrol engines
and are not as widely available. Biodiesel is an oxygenated fuel, meaning that
it contains a reduced amount of carbon and higher hydrogen and oxygen content
than fossil diesel. This improves the combustion and reduces the particulate
emission from un-burnt carbon. Biodiesel is also safe to handle and transport
because it is as biodegradable as sugar, ten times less toxic than table salt,
has a high flash point of about 300oF (148oC) compared to
petroleum diesel fuel, which has a flash point of 125oF (52oC).
(www.eere.energy/gov/cleancities/afde/altfuel)
Current
commercial production of biodiesel (FAME) is via homogeneous transesterification
but this process has a lot of limitations, thus, making the cost of biodiesel
not economical as compared to petroleum-derived diesel. One of the most
significant limitations using this process is the formations of soap in the
product mixture leading to additional cost required for the separation of soap
from the biodiesel. Also, the formation of soap has also led to the loss of
triglycerides molecules that can be used to form biodiesel. However, since the
catalyst and the reactants/products are in the same phase, the separation of
products (biodiesel) from the catalyst becomes complex. On the other hand,
heterogeneous transesterification can overcome all these limitations in which
solid based catalyst is used in place of homogeneous catalyst, making it a more
efficient process for biodiesel production with lower cost and reduced
environmental impact.
Xie
et al. studied the transesterification of soybean oil to methyl ester using
potassium-loaded alumina catalyst. Also, Suppes et al. studied the
transesterification reaction of soybean oil with zeolite and metal catalysts
for the production of biodiesel, while Jitputti et al. studied the
transesterification of crude palm kernel oil and crude coconut oil using
several acidic and basic solids.
All
these study indicated that different oils would require different catalyst for
optimum conversion to biodiesel. {International Conference on Environment 2008 (ICENV
2008)}
1.2 ADVANTAGES
OF THE USE OF BIODIESEL
The advantages of using biodiesel compared to mineral
derived diesel or conventional diesel fuel includes:
1.2.1 EMISSION REDUCTION WITH BIODIESEL
Since biodiesel is made entirely from vegetable oil,
it does not contain any sulphur, aromatic hydrocarbons, metals or crude oil
residues. The absence of sulphur implies a reduction in the formation of acid
rain by sulphate emission which generate sulphuric acid in our atmosphere. The
reduced sulphur in the blend will also decrease the levels of corrosive sulphuric
acid accumulating in the engine crankcase oil over time.
The absence of toxic and carcinogenic aromatics
(benzene, toluene and xylene) in biodiesel implies that the fuel mixture
combustion gases will have reduced impact on human health and the environment.
The high cetane rating of biodiesel (ranges from 49 to 62) is another measure
of the additive stability to improve combustion efficiency.
1.2.2 LOW HYDROCARBON EMISSION
As an oxygen vegetable hydrocarbon, biodiesel itself
burns cleanly, but it also improves the efficiency of combustion in blends with
petroleum fuel. As a result of cleaner emissions, there will be reduced air and
water pollution from engines operated on biodiesel blends.
1.2.3 SMOKE AND SOOT REDUCTION
Smoke (particulate material) and soot (unburnt fuel
and carbon residues) are of increasing concern to urban air quality problems
that are causing a wide range of adverse health effects for their citizens,
especially in terms of respiratory impairment and related illness. The lack of
heavy petroleum oil residues in the vegetable oil esters that are normally
found in diesel fuel means that a boat engine operating with biodiesel will
have less smoke, and less soot produced from unburnt fuel.
1.2.4 REDUCTION IN GREENHOUSE GASES
Unlike other “clean fuels” such as compressed natural
gas (CNG), biodiesel and biofuels are produced from renewable agricultural
crops that assimilate carbondioxide from the atmosphere to become plants and
vegetable oil. The carbondioxide released this year from burning vegetable oil
biodiesels, in effect, will be recaptured next year by crops growing in fields
to produce more vegetable oil starting materials.
1.2.5
POSITIVE ENERGY BALANCE FOR SOLAR ENERGY IN BIODIESEL
Although it takes fossil energy to produce and
transport biofuel, biodiesel has a very favourable energy balance, especially
relative to energy – negative ethanol from corn. Biodiesel production has
positive energy balance ratios ranging from 2.5:1 (institute for local self –
reliance) up to 7.4:1 in Europe, depending on oil crop and distance required to
transport the raw materials. (Singh, 2006), (Margaroni, 1998; Knothe and
Steidley, 2005).
1.3
DRAWBACKS OF THE USE OF BIODIESEL
Despite these advantages, there are several draw backs
that prevent wider use of biodiesel. One of the major drawback is its high
energy consumption and production cost, partly resulting from the complicated
separation and purification of the product. Thus, the production cost is
reduced by performing the reaction without the presence of a catalyst. Other
draw backs include:
1.3.1 GELLING
The cloud point or temperature at which pure biodiesel
starts to gel varies significantly and depends upon the mix of ester and
therefore the feedstock oil used to produce the biodiesel. For
example, biodiesel produced from low erucic acid varieties of canola seed (RME)
starts to gel at approximately -10oC (140oF). Biodiesel
produced from tallow tends to gel at around +16oC (68oF).
As of 2006, there are very limited numbers of products that will significantly
lower the gel point of straight biodiesel. (www.http.web con/biodiesel. html).
1.3.2 CONTAMINATION
BY WATER
The
persistence of mono and diglyceride left over from an incomplete reaction can
result in small but problematic from quantities of water due to attraction from
atmosphere moisture (thus the biodiesel is said to be hygroscopic). In
addition, there may be water that is residual to processing or resulting from
storage tank condensation. The presence of water is a problem because:
Ø It
reduces the heat of combustion of the bulk fuel which in turn enhances more
smoke, harder starting less power.
Ø It
causes corrosion of vital fuel system components; such as injection pumps, fuel
lines, fuel pumps.
Ø It
freezes to form ice crystals near 0oC (32oF), these
crystals provide sites for nucleation and accelerate the gelling of the
residual fuel.
Ø It
accelerates the growth of microbe colonies, which can plug up a fuel system.
Ø Water
can cause pitting in the pistons on a diesel engine.
(www.http.web
con/biodiesel. Html).
1.3.3 PERFORMANCE AND MAINTENANCE PROBLEM
OF BIODIESEL ENGINE
Biodiesel is a better
solvent than petrodiesel and has been known to break down deposit of residue in
the fuel lines of vehicles that have previously been run on petrodiesel. Fuel
filters may become clogged with particulate if a quick transition to pure
biodiesel is made as biodiesel “leans” the engine in the process. Vehicle loses
and filters needs to be checked after six months of operation on biodiesel.
Replacement of non-compatible hoses may be necessary, but it is not usually
difficult or expensive. (Syased, 1998).
1.4 HEALTH
EFFECT OF BIODIESEL PRODUCTION
Research
has been conducted and it was proved that diesel particulate matter is a
potential carcinogen. In 1989, the National Institute for Occupational Safety
and Health (NIOSH) recommended that diesel exhaust be regarded as a potential
occupational carcinogen as defined in the cancer policy of the Occupation
Safety and Health Administration (OSHA). The use of biodiesel decrease most
regulated emissions. Research results indicate that particulate matter
specifically the carbon or insoluble fraction, hydrocarbons and carbon monoxide
are significantly reduced.
Furthermore,
reducing the overall level of pollutant and carbon, the compounds that are
prevalent in biodiesel and diesel fuel exhaust are different. Research
conducted by southwest Research Institute on a Cummins engine indicates that
biodiesel’s exhaust has a less harmful impact on human health than petrodiesel.
Biodiesel
emissions had decreased levels of all target polycyclic aromatic hydrocarbon
(PAH) and nitride PAH (nPAH) compound have been identified as potential cancer
causing compounds. All of the PAH compounds were reduced by 75 to 85 percent,
with the exception of benzo(a)anthracene,
which was reduced by roughly 50%. The target nPAH compound were also reduced
dramatically with biodiesel fuel, with 2-nitrofluorene and 1-nitropyrene
reduced by 90%, and the rest of the nPAH compounds reduced to only trace
levels. All of these reductions are due to the fact that biodiesel fuel
contains no aromatic compound of any kind.
1.5 ENVIRONMENTAL
CONCERN OF BIODIESEL PRODUCTION
The
location where oil-producing plants are groom is of interesting concern.
Monoculture plantations clear cut large areas of tropical forest in order to
grow such oil rich crops such as oil palm. In the Philippines and Indonesia,
such forest clearing is already underway for the production of oil palm. In
Indonesia, for example, deforestation has caused displacement of indigenous
people. Also, in some areas, uses of pesticides for biofuel crops are
disrupting clean water supplies. Loss of habitat on such a scale could endanger
numerous species of plants and animals. A particular concern which has received
considerable attention is the threat to the already shrinking populations of
orangutans on the Indonesian island of Borneo and Sumatra, which face possible
extinction. (www.http.web
con/biodiesel. html).
1.6 TRANSESTERIFICATION OF BIODIESEL
Biodiesel production is the process of
producing the biofuel,
biodiesel, through transesterification or alcoholysis. It involves reacting
vegetable oils or animal fats
catalytically with a short-chain aliphatic alcohols (typically methanol or ethanol).
There
are different basic routes to ester production from oils and fats. These are:
Ø Base
catalyzed transesterifcation of the oil with alcohol.
Ø Direct
acid catalyzed esterification of the oil with methanol.
Ø Conversion
of the oil to fatty acids, and then to alky esters with acid catalysis.
In
order to utilize a vegetable oil in a common diesel cycle engine, without any
need of adaptation in the engine, there is need to transesterify the vegetable
oil, with the aim of lowering its viscosity to a value close to that of
mineral/conventional diesel oil.
Transesterification
in chemistry is the process of exchanging the organic group, R2 of
an ester with the organic group, R1 of an alcohol. These reactions
are often catalyzed by the addition of an acid or base catalyst. The reaction
can also be achieved via enzymes (biocatalysts). (Conceicao et al., 2005).
Transesterification
or alcoholysis involves reacting vegetable oil or animal fat catalytically with
a short – chain aliphatic alcohol (typically methanol). Methanol is the
preferred alcohol for obtaining biodiesel because it is the cheapest and most
available alcohol.
Figure 1.2:
Transesterification reaction
Strong
acids catalyze the reaction by donating a proton to the carbonyl group, thus
making it a more potent electrophile, whereas bases catalyze the reaction by
removing a proton from the alcohol, thus making it more nucleophilic.
The
chemical process above called transesterification involves the separation of
glycerin from the fat or vegetable oil. The process leaves behind two products
– methyl ester (the chemical name for biodiesel) and glycerin (a valuable
by-product usually sold to be used in soap and other products).
(en.wikipedia.org/wiki/biodiesel).
The
reaction between the biolipid (fat or oil) and the alcohol is a reversible
reaction (i.e. an equilibrium controlled reaction), so the alcohol must be
added in excess to drive the reaction towards the right and ensure complete
conversion. The animal and plant fats and oils are typically made of
triglycerides which are esters containing three fatty acids and the trihydric
alcohol, glycerol. In the transesterification process, the alcohol is
deprotonated with a base to make it a stronger nucleophile. Normally, this
reaction will proceed either exceedingly slowly or not at all. Heat, as well as
an acid
or base are used to help the reaction proceed more quickly. It
is important to note that the acid or base are not consumed by the
transesterification reaction, thus they are not reactants but catalysts.
(Freedman and Mount, 2004).
1.7 PROPERTIES
OF BIODIESEL
Some
of the important properties that characterize biodiesel are briefly highlighted
below:
1.7.1 SPECIFIC
GRAVITY
This
method covers the determination of specific gravity (relative density) and
density of crude oil, petroleum products or mixtures of petroleum and non
petroleum liquid products using a glass hydrometer and a mercury in glass
thermometer. This test provides a basis for determining the power required in
pumping and whether the product will or will not float in water. It also gives
an indication of the burning characteristics of the oil.
1.7.2 KINEMATIC
VISCOSITY
Kinematic
viscosity measures the resistance to flow of a fluid under gravity. The
kinematic viscosity is equal to the dynamic viscosity (ratio between applied
shear stress and the rate of shear of a liquid) / density (the mass per unit
volume of a substance at a given temperature).
The
kinematic viscosity is a basic design specification for the fuel injectors used
in diesel engines. However, too high a viscosity, and the injectors do not perform
poorly. The viscosity of biodiesel can be predicted to be ±15% using the esters
composition determined.
1.7.3 WATER
AND SEDIMENT
This
method covers the determination of sediment and water in crude oil, petroleum
products and non petroleum products by centrifuge method.
Water
and sediments is a test that determines the volume of free water and sediment
in middle distillate fuels having viscosities at 40oC in the range
1.0 to 4.1 mm2/s and densities in the range of 700 to 900 kg/m3.
This test is a measure of cleanliness of the fuel. However, water is a usually
kept out of the production process by removing it from the feedstock. Sediment
may plug fuel filters and may contribute to the formation of deposits on fuel
injectors and other engine damage.
1.7.4 FLASH
POINT
The flash
point measures the lowest
temperature at which
application of an
ignition source causes the vapours of the sample to ignite under
specified condition of test. The flash
point is a determinant for flammability classification of materials.
1.7.5 CLOUD
POINT / POUR POINT
The
cloud point is the temperature at which a cloud of wax crystals first appears
in a liquid when it is cooled down under conditions prescribed in the test
method. The pour point is the lowest temperature at which a liquid becomes semi
solid and loses its flow characteristics. The cloud point and pour point is a
critical factor in cold weather performance for all diesel fuels.
1.7.6 CETANE
NUMBER
The
cetane number is
used to evaluate fuels used
in compression ignition
(diesel) engines and
is analogous to
octane number. Cetane
(n-hexadecane) C16 H34 is designated
100 and 0-methyl
naphthalene (C11H10) is designated zero so that
the cetane number
of fuel is
the proportion of
cetane number in a
mixture of these having
the same ignition
delay after injection
of the fuel.
A high speed diesel fuel
may have a cetane number
between 52 and 54 and
a relative density of 0.84.
1.7.7 CALORIFIC
VALUE
The caloric
value of a
fuel is number
of heat units
evolve when unit
mass of a
fuel is completely
burned and the
combustion products cooled
to 288K. In
many respects the
calorific value of
a fuel is
the most important
required before a
fuel can be
used efficiently in
combustion and furnace
plant. A knowledge
and calorific value
of the fuel
to be used
enables the quantity
of fuel for
that required for
that particular duty
to be calculated.
1.7.8 SULPHUR
CONTENT
The
presence of sulphur in fuel is undesirable due to the
fact that it is disastrous to compression process.
In compression process,
sulphur forms its
dioxide and some
trioxide, which may produce
a film of
corrosive sulphuric acid
on parts of
the engine. The sulphur
content can be conveniently measured at the
same time a caloric value is
determined using Mahler bomb calorimeter. This value may be as high as 20%. The
corrosiveness may be determined by observing the colour bands of a strip of
copper immersed in the oil.
1.7.9 CARBON
RESIDUE
The
tendency for diesel oil to form carbon is an important property and is
determined by a carbon residue test. Carbon may be formed by diesel when they
are burnt in the presence of a large excess air or when they are subjected to
evaporation and pyrolysis.
1.7.10 DIESEL INDEX
The
diesel index gives an estimation of the quality based on airline point and the
relative density of the fuel.
Diesel
index = airline point (o F) x relative density (API)
The
airline point of a fuel is the temperature at which equal volume of the fuel
and airline is just miscible. The index indicates the affinity of the fuel, and
since paraffin’s, ignite more readily than any of the other components present,
it gives an indication of ignition characteristics. It is only applicable to
petroleum fuel when there are additives present.
1.7.11 COPPER STRIP
CORROSION
The
copper strip corrosion is used for the detection of the corrosiveness to copper
of fuels and solvents. This test monitors the presence of acids in the fuel.
1.8 USES
OF BIODIESEL
Ø Biodiesel
is preferable for the environment because it is obtained from renewable
resources and has lower emission and pollution hazard when compared to
petroleum diesel. It has less toxic effect than table salt and biodegrades as
fats and sugar. It is used as fuel to run internal combustion engines and it
has a lot of benefits and uses which include:
Ø It
reduces nearly all forms of air pollution compared to petroleum diesel. Thus,
it reduces toxic containing and cancer causing compounds along with the root
associated with diesel exhaust.
Ø It
also reduces greenhouse gases which contribute to global warming. Life cycle
analysis of biodiesel production distribution and use show that biodiesel
produces 78% less of CO2 than petroleum diesel fuel.
Ø Biodiesel being
used as domestic; renewable
source of energy
reduces our dependence
on oil exploration which
therefore improves our
nation and energy
security.
Ø Domestic biodiesel
industry will help
to provide job
and in economic
development.
Ø Biodiesel is easy
to use and produce, it can be used
in existing diesel
vehicle and engines.
1.9 PALM KERNEL OIL AS BIODIESEL
Palm kernel oil (PKO) is edible plant oil derived from
the kernel of the oil palm (Elaeis
Guineensis). Palm kernel oil, coconut oil, and palm oil are three of the
few highly saturated vegetable fats. PKO, which is semi-solid at room
temperature is more saturated and do not contain cholesterol (found in
unrefined animal fats).
PKO
is composed of fatty acids, esterified with glycerol just like any other
ordinary fat. It is high in saturated fatty acids about 80%. The oil palm gives
its name to the 16 – carbon saturated fatty acid palmitic acid found in palm
kernel oil and coconut oil; while kernel oil contains mainly lauric acid.
PKO
is used to prepare biodiesel as either simply processed palm kernel oil mixed
with petrodiesel or processed through transesterification to prepare a PKO
methyl ester blend, which meets the international specification, with glycerin
as a by-product. The actual process used to make biodiesel around the world
varies between countries and the requirement of different export markets.
(en.wikipedia.org/wiki/palm_kernel_ oil). The approximate concentration of fatty
acids in PKO is shown in Table 1.2.
Palm
kernel oil, like other vegetable oils can be used to produce biodiesel for
internal combustion engines. Biodiesel has been promoted as a renewable source
of energy that can reduce net emissions of carbon dioxide into the atmosphere.
Therefore, biodiesel is viewed as a measure to decrease the impact of the
greenhouse effect and as a way of diversifying energy supplies to assist
national energy security plan.
Table 1.2: Approximate Concentration of Fatty Acids in
Palm Kernel Oil
TYPE OF FATTY ACID
|
PERCENTAGE (%)
|
Lauric acid – saturated
C-12:0
|
48.5
|
Myristic – saturated
C-14:0
|
17.0
|
Palmitic acid –
saturated C-16:0
|
7.5
|
Capric acid – saturated
C-10:0
|
5.0
|
Caprylic acid –
saturated C-8:0
|
3.0
|
Stearic acid –
saturated C-18:0
|
2.0
|
Oleic acid – saturated
C-18:1
|
14.0
|
Linoleic acid –
saturated C-18:2
|
1.5
|
Others
|
1.5
|
http://journeytofoever.org/biodiesel
meth.html
The
most important parameters affecting the physical and chemical properties of
such oils are the stereochemistry of the double bonds of the fatty acid chains,
their degree of unsaturation as well as the length of the carbon chain of the
fatty acids.
Previous
studies (the method described by Lang et al, 2001) have shown that palm kernel
oil is non – drying oil rich in lauric acid (12:0) (with iodine value less than
100), contain a high percentage of saturated C-12 and C-14 fatty acids making
it important for the production of surfactant and biodiesel.
Table 1.3: The physio-chemical parameters of PKO
Molecular weight
|
704
|
Density at 40oC
|
0.926
|
Saponification value
(mgKOH/g)
|
250
|
Iodine value (gl2/10g)
|
83.49
|
Acid value (mgKOH/g)
|
8.4
|
1.10 AIMS OF THE STUDY
The
major aim as regards this project work includes the following:
Ø To
produce an alternative fuel for diesel engine that is environmentally friendly
to substitute diesel obtained from petroleum processes.
Ø To
determine the fuel properties of transesterified oil. These properties includes,
Specific gravity (Kg/C), Kinematic viscosity (cSt), Pour point. (oC),
Cloud point (oC), Base sediment and water (%), Total acid number
(mgKOH/g).
1.11 OBJECTIVES OF THE STUDY
Ø To
proffer another possible technique for the production of biodiesel using acid
catalyzed mechanism other than base or enzyme catalyzed mechanism.
Ø To
reduce pollution hazards and biodegradability of the consequences of
petrodiesel to the environment.
Ø To
help strengthen the nation’s economy, should petroleum fuel which is a non
renewable resource be totally consumed or limited in supply.
Ø To
help reduce our reliance on non-renewable fossil fuel.
Ø To
extend the research methodology towards the use of agricultural raw materials
for the purpose of this course as a source of energy.
1.12 PURPOSE OF THE STUDY
There
has been several analytical works on biodiesel production using base catalyzed
mechanism (usually sodium hydroxide or potassium hydroxide) or acid catalyzed
mechanism (usually concentrated sulfuric acid). However, this research work is
centered on the use of acid catalyst (concentrated sulphuric acid) to achieve
the same result (biodiesel production). Therefore, this project seeks to
establish an alternative suitable route to which biodiesel can be produced at a
cheaper cost and environmentally friendly with increased qualities and
characteristics of the fundamental parameters that are to be analyzed when
compared to diesel produced from mineral or conventional oils.
1.13 SCOPE OF THE STUDY
In
this study, the production of biodiesel (FAME) from palm kernel oil (PKO) using
concentrated sulphuric acid as catalyst will be presented. Statistical design
of experiments will be used to accumulate and analyze information on the effect
of process variables on the yield of biodiesel from palm kernel oil, rapidly
and efficiently using minimum number of experiments.
As
illustrated in the later section, this method was found superior than the
conventional method of studying one variable at one time while keeping the rest
constant. Optimization was then carried out to obtain the process variables
that could lead to optimum yield of biodiesel.
Click “DOWNLOAD NOW” below to get the complete Projects
FOR QUICK HELP CHAT WITH US NOW!
+(234) 0814 780 1594
Login To Comment