1

CHAPTER 1

INTRODUCTION

1.0 Introduction

Yanmar Co., Ltd. is a Japanese-based diesel engine and related products

manufacturer that is founded by Tadao Yamaoka at March, 1912 with a

history of more than 100 years. The main office of Yanmar Co., Ltd. is situated

at Osaka, Japan. However, its primary mission of creating a sustainable

lifestyle for humanity marks its branch offices all over the globe including

Brazil, India, China, Malaysia, and more.

Its founder, Mr. Tadao Yamaoka, invented the first horizontal small

diesel engine, which was greatly welcomed by the community especially

agricultural industries where the dependency on animal and labor workforce

was high. By then, the company was named as YANMAR. Subsequently, the

small diesel engine was made commercially viable at 1933 and the name

Yanmar Diesel Co., Ltd. was adopted at 1952, where the world’s smallest 4-

cycle horizontal water-cooled diesel engine was produced. It was awarded

Diesel Gold Medal by the German Inventors’ Association at 1955. Following

that, it was awarded the German Merit Cross and a Japan stone garden

commemorating Dr. Rudolph Diesel was donated to the city of Augsburg,

Germany at 1957. Along the years, Yanmar Diesel Co., Ltd opened several

branches around the world, including Brazil (1957), Indonesia (1972),

Thailand (1978), Netherlands (1988), Singapore (1989), Italy (1995), China

(1999), United States of America (2004), India (2005), Malaysia (2007), Russia

(2007), and United Kingdom (2009). At year 2002, the name “Yanmar Co.,

Ltd” was adopted and is used until now.

2

At 2007, Yanmar Kota Kinabalu R&D Center Sdn. Bhd. is opened as the

first oversea research and development center other than Research &

Development Center, Maibara, Japan. It is located inside the biomass-rich

Asia, where R&D activities focusing on "next generation fuel technologies",

such as biofuels and alternative energies that are both greener and cleaner

for the environment. In addition, researches on the biofuels are also matched

up with development of engine that can perform well with biodiesel.

1.1 Logo

Yanmar Co., Ltd. has a logo (Fig 1) that is a combination of three curved lines

and a capital “Y” letter.

Figure 1.1 Logo of Yanmar Co., Ltd.

The capital “Y” signifies Yanmar Co., Ltd. while the three curved lines signify

the research and development of Yanmar in the field of land, sea, and cities.

As the company’s main production is diesel engine, therefore, it eventually

develops into researching technology for optimizing diesel engine

performance and also development of diesel engine application such

agricultural machinery (land), maritime machinery (sea), and construction

machinery (city).

1.2 Mission and Vision

The corporate principles of Yanmar Co., Ltd. has the mission statement as

“We strive to provide sustainable solutions for needs which are essential to

human life. We focus on the challenges our customers face in food

production and harnessing power, thereby enriching people's lives for all our

3

tomorrows.” A sustainable solution is focused to seek the balance between

humanity developments and environment quality, such as development of

biodiesel-friendly engines so that dependency on diesel, a non-renewable

resource, could be lowered and leads to a greener environment. Moreover,

diesel engine application such as maritime rotary engines are used on fast

boat and public sea transports that shortens the time consumed on

travelling for the passengers. On the other hand, small diesel engines that

are integrated into harvesters also decrease the labor work of farmers and

brings higher yield for the agricultural industries. In addition, development

of geothermal heat pump (GHP) for air-conditioning unit also marks the

mission of harnessing power.

All of these applications are in-lined with the mission statement that

is aimed to solve the challenges of food production and power efficiency, so

that human’s life could be optimized without jeopardizing the environment.

These also match the vision statement of Yanmar Co., Ltd. that is “Grateful

to serve for a better world. To conserve fuel is to serve mankind.”

1.3 Corporate Organization Chart

4

Managing Director (1)

Finance & Adminstrative Group

Manager (1)

Adminstrative Assistant (1)

Accounting Assistant (1)

Maintainence Supervisor (1)

Cleaner/Clerk (1)

Engine Group

Manager (1)

Assistant Manager (1)

Engine Specialist (1)

Engine Technicians

(9)

Fuel Group

Manager (1)

Assitant Manager (1)

Research Officer (0)

Research Assitant (4)

Laboratory Assitant (1)

Sustainability Research Group

Researcher (2)

Directors

5

CHAPTER 2

WEEKLY ACTIVITIES SCHEDULE

2.0 Weekly Activities Schedule

Wee

k

Date

Span

Activities

1 1st - 5th July Briefing of the history and corporate info of

Yanmar Kota Kinabalu R&D Center Sdn. Bhd. along

with the signing of confidentiality letter and

touring of the company building.

Supervised by Ms. Michelle Ni Fong Fong with her

research on transesterification of low quality oil

feedstock.

Learn the basic analyses done in fuel and oil

analysis. Example: Oxidation Stability Index

Induction Period (OSI IP), iodine value (IV),

viscosity test and water content Test.

Learned FTIR spectrometer, Metrohm’s Titrino, Karl

Fisher Titrator, Viscometer bath and Rancimeter,

with reference to the standard operating

procedure (SOP).

Learned and practiced glassware and laboratory

apparatus washing according to SOP.

Introduction and Planning of Yanmar Way of Kaizen

(YWK).

Personal Protective Equipments (PPE) and

Laboratory Safety Briefing.

2 8th – 12th Field trip to company’s Jatropha farm

6

July Sample Analyses (viscosity, water content,

induction period)

Learned basicity test for catalysts and Hammett’s

acidity function.

Photography of samples

3 15th – 19th

July

Sample Analyses (viscosity, water content,

induction period)

Biodiesel production (Basicity test)

Calorific value briefing and analysis

Ester content briefing and analysis

Initiation of mini-project analysis on Petronas, Shell

and Esso diesel samples.

4 22nd – 26th

July

Fuel deterioration briefing and analysis by using

Metrohm Rancimeter

Fuel dilution test briefing and analysis by using gas

chromatography

Biodiesel production (basicity test and ester

content)

Sample Analyses (viscosity, water content,

induction period)

5 29th July –

2nd August

Biodiesel production (homogeneous and

heterogeneous transesterification, basicity test

and ester content)

Company Internship Experience Presentation

6 5th – 9th

August

Biodiesel production (homogeneous and

heterogeneous transesterification, basicity test

and ester content)

Briefing and practice on Ion-exchange of catalyst

7 12th – 16th

August

Briefing and practice on sulfated ash

Biodiesel production (biodiesel washing and ester

content)

Sample analyses (viscosity, water content,

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induction period, density, FTIR)

8 19th – 23rd

August

Briefing and practice on Thermoprep water content

analysis

Briefing and practice on Total Glycerol Content

analysis

Briefing and practice on Methanol Content analysis

CHAPTER 3

SPECIFICATION OF WORKS

3.0 Specification of Works

In YKRC, the job scope is differentiated into two areas i.e. research and

analysis.

3.1 Research

One of the ongoing researches in YKRC is the transesterification of low quality

feedstock into biodiesel. Conventionally, low quality feedstock such as used

cooking oils is hard to be converted as biodiesel. However, by using YKRC

catalyst, the transesterification processes are made possible. I was assigned

in research on transesterification of different types of feedstock by using both

homogeneous and heterogeneous methods. After formation of fatty acid

methyl ester (FAME), ester content is determined to identify the value of

FAME in the biodiesel produced. Heterogeneous method used in YKRC is solid

catalyzed transesterification. Therefore, I also helped in ion-exchanged of

catalyst and basicity test of catalyst.

3.1.1 Tranesterification

8

Transesterification is the process of exchanging the organic group (R”) of an

ester with the organic group (R’) of an alcohol (Eq 3.1).

R'OH +ROCOR→ROH+R'OCOR (Equation

3.1)

This reaction often produces fatty acid alkyl ester. For example, if methanol is

used to react with a given ester, then the products formed are known as fatty

acid methyl ester (FAME), which is the main composition of biodiesel.

Therefore, transesterification is often regarded as biodiesel production.

Generally, transesterification are catalyzed by either a base or an acid

catalyst. In YKRC, biodiesel production focuses more on base catalyzed

transesterification. However, two distinct types of base-catalyzed

transesterification are used i.e. homogeneous transesterification and

heterogeneous transesterification.

In homogeneous transesterification, conventional method is applied,

where sodium hydroxide is used as the base catalyst. Briefly, a required

amount of feedstock is measured by measuring cylinder and poured into a

three-necked flask (Fig 3.1). The flask is then mounted with a thermometer

and a stopper on two of the necks respectively. The feedstock in the flask is

then heated up to more than 50oC but less than 70oC. Depending on the

required weight percentage of the catalyst compared to the feedstock weight,

a certain amount of sodium hydroxide is weighed and dissolved in methanol

by using a stirrer. Then, along with the stirrer, the mixture is quickly poured

into the flask and a condenser is swiftly mounted on the top neck. The

temperature is then maintained between 60oC to 70oC and continuously

stirred for 2 hours.

9

Figure 3.1 Transesterification set up.

For heterogeneous transesterification, instead of using base such as

sodium hydroxide, solid catalyst is used instead. These catalysts are natural

zeolites and synthetic zeolites that have been calcinated and ion-exchanged

as base solid catalyst. The method of heterogeneous transesterification is

similar (including steps, conditions and time usage) to homogeneous

transesterfication. However, instead of dissolving the sodium hydroxide in

methanol, the weighed solid catalyst is dissolved in methanol and poured into

the feedstock.

Heterogeneous transesterification has an advantage of easier recovery

of the catalyst used while also being able to recycle, regenerate and reuse.

On the other hand, homogeneous transesterification can never recycle the

base catalyst used, such as sodium hydroxide. Any excessive catalysts will be

treated as waste. Therefore, heterogeneous transesterification generates less

waste as compared to homogeneous transesterification as sodium hydroxide

is not used.

10

In general, feedstock with high free fatty acids (FFA) percentage has

lower yield of biodiesel; sometimes, even unsuccessful. This is because FFA

hinders the process of transesterification by reacting with the base catalysts

used such as sodium hydroxide. This results in soap formation instead as

there is not enough catalysts to trigger transesterification process. In

industry, feedstock with high FFA, such as waste cooking oil, is first treated

with acid-catalyzed transesterification, where acids, such as sulfuric acid,

catalyze the formation of esters from the FFA and the alcohol introduced.

Then, it is followed by base-catalyzed transesterification. However, by using

two-steps process, this greatly increases the cost and budget of a company.

In addition, greater amount of waste is also be generated. Hence, YKRC aims

to solve the problem by introducing YKRC-zeolites that can process high FFA

feedstock to become FAME with just one step. Often in YKRC, feedstock

samples are mixed with a certain volume of FFA purposely so as to determine

which catalysts and what conditions are suitable to process the feedstock into

biodiesel. In YKRC, feedstock such as nut oil, crude Jatropha oil, refined

bleached deodorized (RBD) palm oil and many more are used in

transesterification.

3.1.2 Ester Content

Before biodiesel could be marketed, the purity of the biodiesel has to be

determined. According to EN14103, the minimum content of FAME in the

biodiesel has to be 96.5% (% m/m).

I practiced on determination of the ester content of several feedstock

include ground nut oil, palm oil and Jatropha oil. In brief, the FAME obtained

from the transesterification process is first washed with hot water. Next, the

washed FAME is stirred and heated at 105oC to remove the water molecules

within. When the FAME turns clear in color, some soap will form due to

hydrolysis. Then, the FAME is filtered by using simple filtration. The filtrate,

which is the washed FAME, is then weighed 250.0 mg into a 10 mL vial. After

11

that, 1 mL of internal standard methyl heptadecanoate (C17:0) is mixed with

the FAME and shakes vigorously. The mixture is then transferred into a 2 mL

GC vial and GC analysis is run. Agilent 7890A GC System (Fig 3.2) is used to

determine the ester content with split/splitless injector, flame ionization

detector and hydrogen as carrier gas.

Figure 3.2 Agilent 7890A GC System

Four samples were transesterified and their ester content determined.

Results (Fig 3.3) shows that ground nut oil, Jatropha oil and palm oil can be

successfully transesterified into biodiesel with high fatty acid methyl ester

content. Castor oil, on the other hand, shows an unexpected low ester

content. It could be due to improper handling of the transesterification

process.

12

Ground Nut Jatropha Oil Palm Oil Castor Oil0

20

40

60

80

100

120

91.5897.88 99.5

79.76Es

ter C

onte

nt (%

)

Fig 3.3 Ester content of four samples transesterified during internship.

3.1.3 Calcination and Ion-Exchange of Catalyst

Calcination is a treatment process for thermal decompositions, phase

transition or removal of volatile fractions in the sample. General functions of

calcinations are i) decomposition of carbonate minerals, hydrated minerals

and volatile matter; 2) inducing phase transitions within the samples through

high temperature; and, 3) removal of ammonium ions in synthesis of zeolites.

In YKRC, calcination is used to unclog the pores of natural and

synthetic zeolites. Often these zeolites contain impurities within the pores, or

some other compounds clog the pores, for example, calcium carbonate. By

high temperature treatment, calcium carbonate is decomposed to calcium

oxide with the release of carbon dioxide. This increases the pores diameters

and eventually led to increase in total surface area of the samples. A higher

total surface area of the zeolites is desired as more ions exchangeable sites

are freed up.

13

Briefly, the zeolites are put into clean crucible after washing. Then, the

zeolites are calcinated at 700oC for 5 hours. After that, the calcinated zeolites

will be ion-exchanged.

Ion-exchange process is used to substitute the ions between two

electrolytes or between an electrolyte solution and a complex. This process is

a reversible process as the samples can be regenerated or load with desirable

ions through excess washing of a particular ion. It is widely used in multiple

industries such as food and beverage, chemicals and petrochemicals,

pharmaceuticals, ground and portable water treatment, softening of industrial

water and more. In YKRC, ion-exchange process is approached to remove

undesired ions within the zeolites, and also load the zeolites with basic

anions.

In general, ion-exchange process is approached by first putting the

desired solid sample into a 100mL centrifuge tube (Fig 3.4). The sample

should be added until the calibrated line of 30mL. Then, a base solution is

added into the centrifuge tube until the calibrated line of 80mL. After that,

the centrifuge tube with the mixture is immersed in a water bath heated at

40-45oC and stirred for 1 hour. After the heating and stirring process, the

mixture is centrifuged for 5 minutes. The clear solution is disposed and the

solid is approached with two more times the ion-exchange process. After all

three times are completed, the mixture is then put into a crucible and heated

at 150oC for 3 hours. After heating, the mixture would become dried. The

solid catalysts are then transferred into a plastic petri dish. The solid catalysts

are then readied for both basicity test and transesterification.

14

Figure 3.4 Diagrams of ion-exchange process

3.1.4 Basicity Test

The solid catalysts that undergone the ion-exchange process become basic in

nature. Hence, it is required to determine the basic strength of the solid

catalysts in order to determine whether the solid catalysts are basic enough

for transesterification process. Basic strength is defined as the ability of the

surface sites to convert adsorbed electrically neutral acids into its conjugate

basic form, which is based on the Hammett’s acid equation (Eq 3.2).

H_ = pKa + log([A-]/[HA]) (Equation 3.2)

In YKRC, basic strength is determined by running titration on the solid

catalyst. First, the solid catalysts are mixed with 10mL of four different types

of hammett’s indicators (Table 3.1 and Fig 3.5) in separate beakers

respectively.

15

Indicators Color at neutral pH

Color at basic pH

pH value

Methyl Orange Red Yellow 3.7

Phenolphthalein

Colorless Purple 9.8

2,4-dinitroaniline

Yellow Slight red 15.0

4-nitrophenol Pink/yellow Slight red 18.4

Table 3.1 Color changes and pH value of selected Hammet’s indicators

Figure 3.5 Color changes of Hammett’s indicator with YKRC catalyst; a) in

phenolphthalein; b) in 4-nitrophenol; c) in 2,4-dinitroaniline; and d) in methyl

orange.

If the catalysts are very basic in nature, it will instantly turn color. For

example, a catalyst that turns colorless phenolphthalein into purple color is

quite basic in nature. On another hand, if a catalyst that does not turn the

colorless phenolphthalein to purple instantly; instead, it occurs by over a

period, and then this catalyst is weak in nature. After that, the solid catalysts

and Hammett’s indicators are stirred for 10mins. Following that, 0.02mol of

benzoic acid dissolved in ethanol is titrated into the mixture. The volume

required to change the color of Hammett’s indicator (for e.g. purple

phenolphthalein) into its original color (for e.g. colorless phenolphthalein) is

noted as the end point. Then, the basic strength is calculated (Eq 3.3).

a) b)

c) d)

16

Basic strengt h (mmol )=V benzoic acid used×0.02mol

mass of sample∈gram(Equation

3.3)

Then, the basic strength of the solid sample with respect to each indicator is

calculated. After that, the total basic strength is calculated by summarizing

the basic strength in each indicator.

Assuming that the color observed when the Hammett’s indicators are

added into the catalysts is equal to 50% conversion of the benzoic acid with

the indicator, the basic strength of the catalyst will be equal to the pKa of the

benzoic acid. Therefore, by using a variety of indicators, the basic strength of

solid catalysts could be determined quickly.

3.2 Sample Analyses

The samples analyzed in YKRC are mainly grouped as biodiesel and

lubricants. Biodiesels, such as palm oil biodiesel, Jatropha biodiesels and

more, are highly regarded as the next fuel source after non-renewable fuel

i.e. petroleum based fuel. It is both renewable and bioenvironmental friendly.

However, the downside of such biodiesels is the lack of stability due to their

readiness to be oxidized. As a R&D company that focuses on developing new

technologies regarding biodiesels, several analyses are required to monitor

the parameters of such biodiesels according to the European Nation (EN)

standards and/or American Society for Testing and Materials (ASTM)

International. These parameters include viscosity, oxidation stability

(induction period), water content, total acid number, peroxide value, iodine

value, CHN value, sulfur value, density, carbon residue, flash point, calorific

value, and boiling point distribution.

As there are two of us begun our internships in YKRC for these three

months, each of us were assigned different analyses. I am assigned with

viscosity, oxidation stability (induction period), water content, density,

17

calorific value, and boiling point distribution. On the other hand, the analyses

carried out by the fuel research group at times are related to the engine

research group. Hence, I was also assigned fuel dilution analysis.

3.2.1 Viscosity

Viscosity, also known as “thickness” of liquid, is the measure of resistance

towards gradual deformation due to shear stress on liquid. It determines how

likely a liquid will flow under given circumstances. There are two types of

viscosity that could be determined for a liquid sample i.e. kinematic viscosity

and dynamic viscosity. Kinematic viscosity is the ratio of dynamic viscosity to

the density of the liquid sample while dynamic viscosity is the measure of

resistance to flow when an external force is applied on the liquid sample.

Figure 3.6 Seta KV-5 Viscometer Bath

In YKRC, the kinematic viscosity of fuel and oil are determined by using

a Seta KV-5 Viscometer Bath (Fig 3.6) according to EN ISO 3104. According to

this standard, the kinematic viscosity is determined by measuring the time

taken for the liquid sample to flow under gravity through a calibrated glass

capillary viscometer (Eq 3.4).

v=C×t (Equation

3.4)

18

where v = kinematic viscosity, C = kinematic constant of liquid sample, t =

time taken.

Then, the dynamic viscosity of the liquid sample could be determined by

relating the density of liquid sample (Eq 3.5).

v=μρ

(Equation

3.5)

where v = kinematic viscosity, μ = dynamic viscosity, ρ = density.

However, the standard used in YKRC only specifies the monitor of kinematic

viscosity; thus, dynamic viscosity is not carried out in YKRC.

Generally, when temperature increases, the resistance to flow of a

liquid decreases, hence, kinematic viscosity of a liquid sample decreases and

become more fluid. The kinematic viscosity of liquid sample is determined

under two temperatures i.e. 40oC and 100oC. Normally, kinematic viscosity at

40oC is the basis of monitoring a liquid sample such as fuel according to the

standard. However, when viscosity index is needed, especially for oil samples,

determination of kinematic viscosity at 100oC is carried out and the

relationship of the kinematic viscosity at 40oC and 100oC is determined.

Viscosity index is the measurement for the change of viscosity of a

liquid sample under variations of temperature (Eq 3.6). It is normally used to

characterize the quality of lubricating oils. As mentioned, viscosity decreases

when temperature increases. If an oil sample has a lower viscosity at high

temperature, the machinery surfaces will come into contact and increases

friction. On the other hand, if the oil is very thick even at high temperature,

the machinery will require a large amount of energy to move. Hence, an oil

will a satisfying viscosity at both low temperature (40oC) and high

temperature (100oC) is highly emphasized. Therefore, viscosity index is used

19

to determine how likely the oil sample will have an unsatisfying viscosity

when temperature changes.

v . i .=100( L−UL−H

) (Equation

3.6)

where v . i . = viscosity index, U = kinematic viscosity, L∧H = values based

on kinematic viscosity at 100oC.

As mentioned, capillary glass viscometers are used to determine the

liquid sample. Based on different types of samples, different types of

viscometers are used (Fig 3.7). For fuel (diesel and biodiesel) samples, a U-

tube is used as the liquid is clear and will not obscure the analyst when

determining the movement of liquid passing through the calibrated mark. On

the other hand, oil samples (lubricants) are dark colored; thus, an opaque

tube is used as it allows easy determination of the samples. Other than that,

different viscosities of liquids require different types of tubes i.e. 100, 200,

300 and 400 tubes, where more viscous liquids will require a higher number

of the tube.

Figure 3.7 U tube (left) and opaque tube (right). U tube is used for fuel

samples which are clear and transparent, allowing determination of the

flowing of liquid passing through the calibrated mark easily through

20

gravitational pull. For opaque tube, the oil sample is first vacuum sucked into

the reservoir bulb, and the flowing of sample is easily determined as it moves

upward of the tube by filling the tube.

I practiced viscosity test on samples (i.e. Jatropha oil and palm oil)

stored on open-bottle condition and closed-cap condition. The results (Fig 3.8)

show that over the time of storage, viscosity of samples increases. This could

be caused by air oxidation as oxidation process causes the samples to

thicken. Comparing both open-bottle and closed-cap condition, it could be

seen that closed-cap condition resists the change in viscosity in a higher

efficiency than open-bottle condition. This is due to the lesser interaction of

air with the oil sample.

Figure 3.8 Viscosity of samples stored in different condition over ten

months.

3.2.2 Oxidation Stability (Induction Period)

Fuel and oil samples are organic compounds. Biodiesels, especially, are series

of unsaturated hydrocarbons. These hydrocarbons are susceptible to

oxidation process, where oxidized fuel and oil samples are termed as

deteriorated. A series of oxidized products will form such as acids and

polymers due to free radical reactions. These oxidized products will cause

clogging on plugs and filters of machinery, eventually reduces the efficiency

of the concerned machines. Therefore, it is required for fuel and oil analysis

to determine the stability of a sample toward oxidation.

According to EN 15751, oxidation stability is the period when 50% of

the sample is oxidized. On the other hand, induction period is the period from

the start of measurement to the first rapid formation of oxidized products. In

YKRC, induction period is determined by using Metrohm Rancimeter (Fig 3.9).

21

Figure 3.9 Metrohm Rancimeter.

Based on the standard, 10L/hr of dry air is purged through the liquid

sample at a temperature of 110oC. The oxidized products are volatile and will

move from the measuring vessel into the reaction vessel where the

conductivity is recorded. There are two types of measuring vessels i.e. a short

measuring vessel and long measuring vessel (Fig 3.10). Depend on different

types of measuring vessels, the conditions, such as weight of sample used

and volume of deionized water used on the reaction vessels, vary. For short

measuring vessel, 3.0 g of sample and 50.0 mL of deionized water are used.

On the other hand, 7.5 g of sample and 60.0 mL of deionized water are used

for long measuring vessel.

Figure 3.10Short (left) and long (right) measuring vessel. A short measuring

vessel is intended for biodiesel samples, while long measuring vessel is

intended for diesel samples.

I practiced induction period on Jatropha oil and palm oil samples. The

results (Fig 3.11) show that induction period of the samples decreases over

22

time of storage. This implies that the samples could not resist oxidation

efficiently over time and hence the time taken to induce first oxidation

products shortens over time. Similar to viscosity test, closed-cap condition

shows a better efficiency in resisting the oxidation process as it has limited

air molecules to interact with since the cap is closed.

Mon

th 0

Mon

th 2

Mon

th 4

Mon

th 6

Mon

th 8

Mon

th 1

0

0

5

10

15

20

25

Closed-cap Jatropha Oil

Closed-cap Palm Oil

Open-bottle Jatropha Oil

Open-bottle Palm Oil

Time of Storage

Ind

ucti

on

Peri

od

(h

r)

Figure 3.11 Induction period of samples stored in different condition over ten

months.

3.2.3 Water Content

Biodiesel has high hydrophilicity; it attracts water easily. Presence of water

within biodiesel is a troublesome situation as water content promotes the

growth of microbes as biodiesel is a very ideal nutrient base. Growth of

microbes will result in clogging of fuel pump, filter and more. Other than that,

water content also reduces the heat of combustion of the fuel, resulting in

more exhaustion smoke, less power and harder starting of the engine.

According to EN 14214, water content in fuel/oil sample is determined

by using coulometric Karl Fischer titration method (Figure 3.12).

23

Figure 3.12Coulometric Karl Fischer titrator (left); schematic diagram of KF

titrator (right). The titrator has two chambers i.e. the cathode and the anode

chambers. The sample is directly injected into the anode solution and iodine

is generated at the generated electrode. Generated iodine will react with

water molecules in sample to produce iodide ions. During equivalent point,

excess iodine molecules are present as there is no more water molecules to

react with the iodine molecules. The measuring electrode will then measure

the current needed to achieve such amount of iodine molecules, and is

marked as end-point.

A small weighted sample is injected into the Karl Fisher titrator, which

contains chloroform and Hydranal mixture. Chloroform is used to dissolve the

fuel/oil sample while Hydranal contains the reagents (an alcohol, a base,

sulfur dioxide and iodine) that will react with the water molecules. During the

chemical reactions, one molecule of iodine will be liberated at the anode as

iodide ion with one molecule of water consumed (Eq 3.7 & Eq 3.8) when

current passed through.

B∙ I 2+B ∙SO2+H 2O+B→2BH +¿ I−¿+BSO3 ¿¿ (Equation

3.7)

BSO3+ROH→BH +¿ROSO3−¿¿ ¿ (Equation

3.8)

24

The end point of the chemical reaction is detected by

bipotentiometric method, where a second electrode is immersed in the anode

solution and both have a constant current maintained between the two

electrodes. Before equivalence point, the water molecules in the sample

actively engaged iodine molecules, causing the solution to contain iodide

ion but little iodine molecules. However, at equivalence point, excess iodine

molecules appear resulting in an abrupt voltage drop, which marks the end

point. Therefore, the amount of current needed to generate the required

amount of iodine molecules to reach the end point is then used to calculate

the amount of water in the injected sample.

Similar to the tests before, Jatropha oil and palm oil samples are tested

on water content analysis. The results (Fig 3.13) show that water content of

the samples increase over time. This shows that over time of storage, the fuel

absorbs more water molecules into the liquid. This could be due to the

formation of peroxide molecules and acid molecules during oxidation process

as they are highly hygroscopic. Comparison between open-bottle condition

and closed-cap condition, similar to viscosity test and induction period test,

show that closed-cap condition has a lesser increment in terms of water

content as the sealed condition limited the amount of water molecules to be

interacting with the samples.

25

Mon

th 0

Mon

th 2

Mon

th 4

Mon

th 6

Mon

th 8

Mon

th 1

0

0

500

1000

1500

2000

2500

Closed-cap Jatropha Oil

Closed-cap Palm Oil

Open-bottle Jatropha Oil

Open-bottle Palm Oil

Time of Storage

Wate

r C

on

ten

t (p

pm

)

Figure 3.13Water content of samples stored in different condition over ten

months.

3.2.4 Density test

Density is a specific physical characteristic of matter. By checking the density

of a substance, the purity of the substance could be safely assumed. In fuel

and oil analysis, ASTM D4052 is used as a standard test method for density

and relative density of liquid by using a digital density meter. According to

the standard, the density or relative density of petroleum distillates and

viscous oils is determined at test temperatures range from 15oC to 35°C. The

standard also only restricted to the density determination of liquids with

vapor pressures less than 600 mm Hg (or equivalent to 80 kPa) and

viscosities lower than 15 000 mm2/s.

In YKRC, Anton Paar DMA 535N Density Meter (Fig 3.14) is used to

determine the density of fuel and oil samples.

ON key

Display

Sample cell

Pump

Tube

26

Figure 3.14Anton Paar DMA 535N Density Meter

Briefly, the density meter is on before analysis is done. Next, the pump is

pressed fully and the tube connected to the density meter is immersed in

washing agent such as toluene as toluene is a suitable solvent to dissolve fuel

and oil sample. Then, the pump is released slowly and the solvent should be

sucked into the sample cell. It is to be noted that the sample cell should be

completely filled with the solvent without air bubbles. Then, the liquid is

pumped out and washing is repeated for twice or until no indication of

samples within. After that, washing is continued with acetone as traces of

toluene within the sample cell have to be washed away. Acetone is also a

highly volatile liquid that it will vaporize very quickly afterward. Then, the

tube is immersed in a sample to be determined. Repeating the pumping and

releasing, the sample is sucked into the sample cell and it must be confirmed

that there are no air bubbles within the sample cell as air bubbles

significantly affect the determination of density. Following that, a reading of

density and temperature of the liquid is displayed. When the temperature

stopped blinking, then the density value is recorded. After analysis is

completed, the density meter tube is washed in the same fashion as above.

The density values displayed in the density meter are with respect to

the temperature of the liquid. However, ASTM D4052 requires a value of

27

density at 15oC as the standard guidance. Hence, calculation has to be done

for the density value to be converted to density value at 15oC (Eq 3.9)

ρ15=ρT+0.723(T−15) (Equation

3.9)

Where T = temperature the reading is taken.

Jatropha oil and palm oil samples are tested on density test (Table 3.2).

SampleDenisty (kg m-

3)

Jatropha

Oil921

Palm Oil 920

Table 3.2 Density of samples tested in YKRC.

Both test results are confirmed with Zhou et al. (2006), who states that the

density of Jatropha oil is 900 kg m-3 at 25oC, and Sultanar Yasser (2012), who

states palm oil as having 907 kg m-3 at 25oC.

3.2.5 Carbon Residue Test

Carbon residue of a fuel is the tendency of carbon deposits to form under

high temperature of combustion in an inert atmosphere, such as in nitrogen

atmosphere. It is shown that there is a negative impact when carbon residue

exists in diesel engine. Therefore, a carbon residue test is used to indicate the

carbonaceous deposit-forming tendencies of the fuel.

ASTM D4530, Standard Test Method for Determination of Carbon

Residue (Micro Method), is used to determine the amount of carbon residue

28

formed after evaporation and pyrolysis under inert atmosphere. It is used to

provide indication of the relative coke forming tendency. Carbon residue test

serves as an approximation of the tendency of the material to form

carbonaceous type deposits under degradation conditions. In YKRC, SETA

Micro Carbon Residue Tester (Fig 3.15) is used to determine the carbon

residue of sample.

Figure 3.15SETA Micro Carbon Residue Tester

In brief, the vials are pre-heated in an oven at 80oC for 1 hour to

remove contaminants and moisture content. A hook (Fig 3.16) must be used

to hook and unhook the vials container to ensure no contaminants transferred

on the vials as it might affect the reading during weighing.

Figure 3.16Hook and vials used for carbon residue test.

After pre-heating, the vials are cooled to room temperature in a dessicator.

After that, the vails are weighed in the beam balance. The weights of vials are

Hook

Vials

29

recorded and 5.0 g samples are weighed into the vials. Then, the vials, along

with the container, are put into the micro carbon residue tester to be

combusted in nitrogen atmosphere in 553oC for 20 minutes. Cares have to be

taken that the lid of the tester has to be fully closed else explosion might

occur. After the temperature has cooled down below 100oC, the vials are

transferred to a dessicator to be cooled down. Finally, the vials are weighed

again and the values are recorded. The carbon residue is then calculated in

mass percentage (m/m %) (Eq 3.8).

Carbonresidue (m /m% )=massof residuemassof sample

×100% (Equation

3.9)

The carbon residue value of three commercial diesels sold in Malaysia

is determined (Fig 3.17). The results show that commercial diesel 2 has a

higher carbon residue value, while the rest of the two are around 0.004-

0.005%. The difference in residue value might arise due to differences in

production methods.

Commercial Diesel 1 Commercial Diesel 2 Commercial Diesel 30

0.002

0.004

0.006

0.008

0.01

0.012

0.014

0.016

0.005

0.015

0.004

Carb

on R

eisd

ue (%

m/m

)

30

Figure 3.17Carbon residue value of three different commercial diesels sold

in Malaysia.

3.2.6 Calorific Value

Fuel is combusted in engine and the energy released is used to drive the

pistons within engine, which in turn drive the mechanical energy required by

the vehicle to move. Therefore, calorific value of fuel samples has to be

monitored as less calorific value fuels tend to burn inefficiently and thus

produces higher amount of exhaust which leads to air pollution.

Calorific value is determined by using ASTM D4809, which is the

Standard Test Method for Heat of Combustion of Liquid Hydrocarbon Fuels by

Bomb Calorimeter. According to this standard, a weighed sample is burned in

an oxygen-bomb calorimeter, where the energy released during the

combustion is absorbed by the water bath surrounding the bomb. As the

water molecules absorbed the energy, temperature increases and the heat

change is determined. In YKRC, IKA Calorimeter C2000 (Fig 3.18) is used. This

instrument is a type of isoperibol calorimeter, where a static water jacket is

used to insulate the water bath, which contains the bomb. The water jacket is

kept under a constant temperature by using IKA KV 600 Digital water cooler.

Figure 3.18 IKA Calorimeter C2000 and KV 600 Digital water cooler.

KV 600 Digital water cooler

IKA Calorimeter C2000

Seal cap

Thread

Depressurizer

Bomb canister

Sample Soup

31

In brief, 1.00 g of sample is weighed in the sample sup (Fig 3.19). Next,

a cotton thread is connected to the sample sup and serves as an ignition

point. Then, the bomb is assembled by putting the sample sup within the

bomb and sealed tight. After that, the bomb is inserted to the calorimeter.

After the sample weighed has been keyed into the calorimeter, “START”

button is clicked and the bomb will be immersed into the water bath and the

calorimeter will be sealed. Analysis normally takes 30 minutes to complete.

After completion, the display will show the calorific value of the sample

analyzed. The bomb will be ejected out of water bath. At this stage, the bomb

is highly pressurized; hence, a depressurizer is used to release the pressure

of the bomb. Then, the bomb is dismantled and wiped clean before next

analysis.

Figure 3.19Schematic diagram and actual diagram of bomb canister for

bomb calorimeter.

Calorific values of several samples are tested. Results (Fig 3.20)

showed that diesel samples generally have higher calorific value than the

biodiesel. However, as the current economy employs usage of blended

biodiesel, which are either B5 or B20, the effect of less calorific value of the

biodiesel is not significant.

32

0

6000

12000

18000

24000

30000

36000

42000

48000

39514 39887

45975 46090 45576

Jatropha OilPalm OilCommercial Diesel #1Commercial Diesel #2Commercial Diesel #3

Calo

rific V

alue

(J/g

)

Figure 3.20Calorific values of different samples.

3.2.7 Methanol Content Analysis

Methanol is a by-product of biodiesel production, which occurs as excessive

reagent that could not be washed off completely during biodiesel washing.

According to EN14110, maximum amount of methanol within a biodiesel is

0.20 % (m/m). This is because methanol is highly volatile and results in higher

vapor pressure of the fuel. This causes the fuel to be highly flammable and

hard to be stored. Agilent 7890A GC System (Fig 3.21) is used to determine

the methanol content. As methanol is highly volatile, headspace sampling

method is used.

Figure 3.21Agilent 7890A GC System and 7694E Headspace Sampler

33

I practiced the calibration procedure of methanol content analysis.

Briefly, a QC-graded palm oil sample is transferred to the calibrated mark in a

10 mL volumetric flask. Next, 112 μg of methanol is added into the volumetric

flask. The volumetric flask is shook vigorously to homogenize the mixture.

Then, 5 mL of the mixture is transferred into another 10 mL volumetric flask

and the QC-graded palm oil sample is added to the calibration mark. The

mixture is, again, shook vigorously. Lastly, 1 mL of the mixture in the 2nd

volumetric flask is transferred to a 3rd 10 mL volumetric flask and calibrated

with QC-graded palm oil sample. Three mixtures with concentration

percentage of 5.0%, 1.0 % and 0.1% are produced. Then, each mixture is

transferred to a 20 mL headspace vial respectively. After that, the headspace

vials are inserted into a headspace sampler, which is set to vaporize the

sample at 80oC during injection so that methanol will be liberated. GC system

is using a split/splitless injector with hydrogen as carrier gas.

The detector of GC is flame ionizing detector. The 7694 headspace

sampler and GC system are computationally fixed to communicate between

injections so that the injector will not sample the methanol when there is a

run ongoing in the GC system. Finally, a calibration chromatogram (Fig 3.22)

is obtained and the calibration curve graph is calculated. The graph shows a

very good correlation factor at 0.99989 and hence could be used for actual

sample determination.

Figure 3.22Chromatogram of methanol content calibration (left) with the

calibration curve graph (right).

34

3.2.8 Fuel Dilution Analysis

Fuel is directly injected to the diesel engine. Then, compression from piston

leads to combustion. Overtime, some fuels are not combusted completely and

will stick on the wall of the engine. These fuel droplets will eventually drop

down to the lubricating oil of engine by being pulled by piston. These fuels

then dilute the lubricating oil of engine and leads to poor performance of

lubricants as dilution causes less viscous lubricants. ASTM D3524 is used to

determine how dilute is the engine lubricating oil so as to monitor a constant

inner environment of the engine.

Agilent 7890A GC System (Fig 3.23) is the main instrument used to

identify the fuel dilution in diesel engine. Cool-on column injector is used with

helium as the carrier gas. Automated liquid sampler is used as sampling

method and flame ionizing detector is used as the detector. In brief, 1.0 g of

n-decane is transferred to a short measuring tube of Metrohm Rancimat,

which acts as the internal standard to compare to the fuel within the sample.

Next, 10.0 g of fuel diluted lubricating oil is transferred into the tube

containing n-decane and homogenized on a vortex machine for 30 second.

Then, 0.5 g of the mixture is transferred to a 10 mL volumetric flask and top

up with the solvent, carbon disulfide, to the calibrated mark. After that, the

mixture is shook vigorously and transferred into a 2 mL GC vial.

Figure 3.23Agilent 7890A GC System

35

A chromatogram (Fig 3.24) is obtained after the analysis is completed.

The peak area of diesel component is then compared to the peak area of n-

decane. The ratio (Eq 3.10) is then calculated to give the percentage of fuel

dilution.

Figure 3.24A typical fuel dilution chromatogram.

Ratio= peak areaof dieselpeak area of n−decane

(Equation 3.10)

In YKRC, fuel dilution percentage is used to monitor how diluted is the

lubricating oil in engine, which the project aims to identify at what dilution

percentage that the engine performance will decrease. As the current aim is

to determine the performance of engine in fuel dilution percentage at 20%,

the engine lubricating oil is monitored to remain in 20% range. If the dilution

percentage is low, then fuel is added into the lubricating oil to ensure it stays

at 20% value. Then, the dilution value will rise and over the time of running,

will decrease again. After that, the top-up of fuel is repeated (Fig 3.25).

36

Run 1

Run 2

Run 3

Run 4

Run 5

Run 6

Run 7

Run 8

Run 9

Run 10

Run 11

Run 12

Run 13

Run 14

Run 15

Run 16

Run 17

Run 18

Run 19

0

5

10

15

20

25

30

Fuel

Dilu

tion

(%)

Fig 3.25 A typical fuel dilution graph plotted over a run of twenty times.

3.2.9 Total Glycerol Content

During production of biodiesel, transesterification occurs. Triglycerides react

with methanol to form fatty acid methyl ester (FAME). When the 1st glycerin

reacts with methanol, diglyceride is formed and 1 molecule of FAME is

released. When the 2nd glycerin reacts, monoglyceride is formed and another

1 molecule of FAME released. When the monoglyceride reacts with methanol,

glycerol is produced and releases last molecule of FAME. In biodiesel

production, sometimes the triglycerides do not react completely. According to

EN14105, monoglyceride, diglyceride, triglyceride, and free glycerol content

are kept maximum in 0.80 % (m/m), 0.20 % (m/m), 0.20 % (m/m) and 0.02 %

(m/m) respectively. Therefore, determination of the total glycerides content

and glycerol content helps to understand how well the conversion of

transesterification process is.

I practiced the calibration procedure for total glycerol content in YKRC.

Agilent 6890N GC System (Fig 3.26) is used to determine total glycerol

content, with cool on column as the injector, flame ionizing detector as

detector and hydrogen as carrier gas.

37

Figure 3.26Agilent 6890N GC System

For calibration mixture preparation, standards graded monoglyceride,

diglyceride, triglyceride, 2,4-butanediol, tricaprin, and glycerol are used. Four

different concentration mixtures are prepared with respective ratio of mixture

(Table 3.3) and mixed in four different 10 mL volumetric flasks respectively.

Next, 100 μL of N-methyl-N-(trimethylsilyl)trifluoroacetamide is mixed into

each of the volumetric flask and shake vigorously. Then, the flasks are sit still

in room temperature for 15 minutes. After that, 8 mL of solvent (n-heptane) is

mixed into each of the flask. The mixture in each flask is then transferred into

2 mL GC vials and set to run for GC analysis.

Standard (μL) 1 2 3 4

Glycerol 10 40 70 10

0

Monoglyceride 50 12

0

19

0

25

0

Diglyceride 10 40 70 10

0

Triglyceride 10 30 60 80

Butanediol (STD

#1

80 80 80 80

Tricaprin (STD

#2)

10

0

10

0

10

0

10

0

38

Table 3.3 Mixing ratio of each standard.

A calibration chromatogram (Fig 3.27) is then obtained which showed

unsatisfying curves due to noisy peaks. Hence, the calibration is re-run again

by another operator and the graphs are compared. The in-house calibration

graph is clearer and with minimal noise. Then, a series of calibration graphs

(Fig 3.26)is plotted and the correlation factors all show satisfying values;

hence, it could be used in actual sample determination.

Figure 3.27Comparison of in-house calibration chromatogram (above) with

the calibration chromatogram that I produced (below).

71

23

4 56

SolventGlycerolButanedienolMonoglycerideTricaprinDiglycerideTriglyceride

1

234

5

6 7

39

Figure 3.27Calibration curve graphs for in-house methanol content

calibration chromatogram.

40

References:

Zhou, H., Lu, H.F. & Liang, B. 2006. Solubility of Multicomponent Systems in

the Biodiesel Production by Transesterification of Jatropha curcas L. Oil with

Methanol. J. Chem. Eng. Data, 51(3):1130 – 1135.

Sultana Yasser. 2012. Density Table for Palm Oil Products.

Retrieved on, 11th September 2013

From, http://sultanayasser.blogspot.com

41

CHAPTER 4

CONCLUSION

In conclusion, I learned a great deal of laboratory skills and techniques

especially involved in chemicals and apparatus handling. I learned

instrumental techniques of gas chromatography and also transesterification

processes. In addition, I also learned various analyses such as viscosity test,

water content test, induction period test, density test, calorific value test, and

carbon residue test. Other than that, I learned of proper procedures in

scheduled waste disposal. Three months of experiences in Yanmar Kota

Kinabalu R&D Center S/B is very fulfilling and challenging. I will definitely

suggest YKRC as one of the companies that fit for internship learning.