LUBRICATING PROPERTIES OF MIXTURE OF TWO

SELECTED VEGETABLE BASED LUBRICANTS.

BY

OGUNNIGBO, Charles Olawale.

A THESIS PROPOSAL SUBMITTED IN PARTIAL

FULFILLMENT OF THE REQUIREMENT FOR THE DEGREE

OF

MASTERS OF SCIENCE

In Mechanical Engineering.

OBAFEMI AWOLOWO UNIVERSITY,

ILE-IFE, OSUN STATE.

October, 2013.

CHAPTER ONE

1.0 BACKGROUND INFORMATION.

Tribology is defined as “the science and

technology of surfaces interacting in motion”. Thus it is

important for us to understand the surface interaction when

they are loaded together as to understand the tribology

process occurring in the system. The physical, chemical and

mechanical properties not only cause the effect to the

surface material in tribology behaviour but also the near

surface material.

The continued growing environmental concerns are

providing impetus for increased demand and usage of

vegetable oil utilization in lubricants from many

applications. Of the 5 – 10 million tons of petroleum based

oleo chemicals entering the biosphere every year, about 40%

comes from spills, industrial and municipal waste, urban

runoff, refinery process, and condensations from marine

engine exhaust (1). Meanwhile, vegetable based oil can offer

significant environmental advantages with respect to:

Resource renewability.

Biodegradability.

Adequate performance in a variety of applications and

non toxicity.

High viscosity index.

Affordable application cost.

Good lubricity.

1.1 LUBRICITY.

The term “lubricity” refers to the slipperiness of

lubricant films formed in boundary lubrication, a condition

which lies between unlubricated sliding and fluid – film

lubrication and which is also defined as a condition in which

the friction between the surfaces is determined by the

properties of the surfaces and properties of the lubricants

other than viscosity. Boundary lubrication encompasses a

significant portion of lubrication phenomena in metalworking

operations.

The main function of lubricants in tribological

systems is to reduce friction and wear. The reduction of

friction and wear result in the formation of a lubricant film

separating the rubbing surfaces. The thickness of the

lubricant film depend upon constituent chemistry (base oil and

additives), as well as upon the operating conditions,

especially the applied load and sliding velocity. At a

significant high load, lubricants may be expelled from the

friction zone, leaving the rubbing surface unlubricated. In

this case, severe friction and wear occur.

To alleviate the dramatic effect of “dry” friction,

extreme pressure (EP) additives are deployed. Those additives,

normally containing sulphur, phosphorus, chlorine or

molybdenum derivatives, are capable of reacting with the

material of rubbing surfaces to form a thin surface layer of

chloride, phosphate or sulphide, which act as a solid

lubricant when the rubbing surfaces comes into a direct

surface – to – surface contact with each other (2). The

accumulation of scars when unlubricated sliding occurs gives

room to wear.

Lubricants can be classified into two general categories

as engine and non – engine. The two categories are:

Engine Lubricants.Non – engine Lubricants.

Gasoline engine oilsTransmission fluids

Diesel engine oilsPower steering fluids

Automotive diesel oilsShock absorber fluids

Railroad diesel oilsGear oils

Natural gas engine oilsHydraulic fluids

Aviation engine oilsMetalworking fluids

Two – stroke engine oils. Etc.Greases. Etc.

1.2 PALM OIL AS A VEGETABLE BASED LUBRICANT.

Palm oil is an edible vegetable oil that comes from oil

palm trees (elaes guineesis) is a major industrial commodity

that is used in a range of consumer goods, from oleo chemicals

to bio fuels. The oil is derived from fruit of the oil palm

tree, which grows in large, reddish clusters and is roughly

the size and shape of plum. The oil palm fruit can be used to

produce two separate kind of oil: “Palm oil” which refers to

the oil extracted from the fresh of the fruit, and “Palm

kernel oil” which refers to the oil extracted from the seed at

the centre of the fruit. Though they both come from the same

plant, these two oils have different properties and uses. A

principal difference is in the saturated fat content of the

two oils: Palm oil is approximately 50% saturated fat, while

Palm kernel oil is over 80% saturated fat (3).

1.3 GROWTH of PALM OIL.

Today, palm oil is the most widely used vegetable oil in the

world. As shown in the chart below, palm and palm kernel oils

accounted for 35% percent of total vegetable oil production in

2011. At 27% of total production, soybeans were the next

largest source of vegetable oil, followed by rapeseed (the

basis of canola oil).

Part of the reason for palm oil’s widespread use is the fact

that oil palms are a highly efficient source of vegetable oil.

On a per hectare basis, oil palms produce roughly ten times as

much vegetable as soybeans. Their high outputs keep production

costs relatively low, making them one of the most affordable

sources of vegetable oil available. On top of this, palm oil

is a versatile substance, with chemical properties that make

it applicable for a wide range of consumer goods. Finally,

palm oil, unlike other vegetable oils, does not contain any

Tran’s fats, which have been linked to heart disease and other

health risks. For these reasons, palm oil can be found in

roughly 50% of all supermarket products in many developed

markets, according to the WWF.

1.4 STATEMENT OF PROBLEM.

Ecological factors are gaining importance in our

society. Bearing in mind that our environment is being

increasingly contaminated with all kinds of pollutants, any

reduction is welcome. From an environmental point of view, and

compared to a number of other chemical products, lubricants

are not particularly problematic although a worldwide increase

in concern over the health – related and environmental effects

of petroleum oil, as well as its limited supply, has generated

interest in the use of biodegradable products. A large

proportion of lubricants pollute the environment either during

or after use. It has been stated that 5–10 million tons of

petroleum-based oleo chemicals enter the biosphere every year.

About 40% comes from spills, industrial and municipal waste,

urban runoff, refinery processes, and condensation from marine

engine exhaust. These oleo chemical pollutants are derived

from the food industry, petroleum products, and by-products

such as lubricating, hydraulic, and cutting oils. The

terminology used in connection with environmental

compatibility can be split into two criteria, i.e., subjective

and objective. The non-measurable or subjective criteria are

environmentally friendly and environmentally compatible. The

objective criteria, among others, include biodegradability,

water solubility, ecological toxicity, efficiency

improvements, etc. Normally a biodegradability of at least

60%, according to OECD 301, is considered the main objective

criterion for bio-lubricants. One of the possible lubricants

that can satisfy this need is vegetable oil, which can offer

significant environmental advantages with respect to resource

renewability, biodegradability, and adequate performance in a

variety of applications (4).

1.5 OBJECTIVES OF THE RESEARCH.

The major objective of this research is to investigate

the lubricating properties of a mixture of RBD palm

steerin with palm olien using a locally made tribotester.

Also to compare the effect of temperature on friction and

wear performance of vegetable based lubricant mixture

(i.e. palm steerin and palm olein), and additive – free

paraffinic mineral oil.

1.6 SCOPE OF THE RESEARCH.

A detailed study of past thesis shall be conducted to

carry out investigation as to the possible area of research.

The materials needed to determine the lubricating properties

shall be gathered. The palm oil shall also be collected, both

RBD palm steerin and palm olein from local sellers.

To carry out the lubricating properties such as wear and

friction, a tribotester will be used. And since a tribotester

is not presently available, a locally machined tribotester

shall be improvised to carry out the experiment. A

mathematical relation shall be used to determine the

coefficient of friction of each test lubricant. More so, at a

constant angular speed and load for a period of time, the wear

scar diameter on the materials in the lubricant will be

determined using a Scanning Electron Microscope {SEM}. The

coefficient of friction and wear for the vegetable based

lubricant shall be compared to the conventional paraffinic

mineral oil to determine their efficiency.

CHAPTER TWO

2.0 LITERATURE REVIEW.

Previous research has confirmed that a primary source of

environmental pollution is the burning of mineral and its

entrance into the ecosystem (Grant et al., 2008, Mercurio et

al., 2004, Bartz, 1998).biodegradable oils are becoming an

important alternative to conventional lubricants as a result

of the increased awareness of ecological pollution. Vegetable

oil, including animal fat, was used as a lubricant thousand of

years ago. In ancient Egypt, vegetable oils were used in the

construction of monument (5).

Masjuki investigated the influence of wear and friction of

blended palm oil methyl ester lubricant using a four-ball

tribotester and indicated that, at lower loads and

temperatures, the wear rate using palm oil methyl ester

lubricant was low, under 5%, but in higher loads, the wear

rates increase (Masjuki. H. H, 2000).

The lubricity of a vegetable oil-based lubricant was

investigated using high frequency reciprocal testing to

examine viability as a diesel fuel blend/ bio-oil. Results

showed that the average friction coefficient of bio oil was

less than blended diesel fuel; the amount of friction

coefficient of the bio-oil was 0.130 and diesel oil was

0.164(Xianguo Hu, 2010). Jatropha oil, which is derived from

Jatropha seeds and found in many countries, such as Malaysia,

Indonesia and Thailand, is considered a possible alternative

to mineral oil. Thus, the use of vegetable oils as a lubricant

in the industrial sector is not a new idea. For the last three

decades, the lubrication industry has been trying to formulate

environmentally friendly lubricants with technical

characteristics equal to those of mineral oil. Vegetable oils

have lubricating abilities that are better than those of

currently used mineral or synthetic oils because of the large

amount of unsaturated and polar ester groups they contain, as

reported by Alla and Richards (6). Kalin and Vizintin (7)

explained that these components maintain the desired

conditions during reciprocating sliding. In the early 20th

century, the Malaysian Palm Oil Board (MPOB) successfully

created palm oil methyl ester from crude palm oil using

transesterification. The transesterification method shortened

the molecular chain in the palm oil from about 57 to 20

molecules, thus improving the palm oil by reducing its

viscosity and making it less polluting. Furthermore, Masjuki

and Maleque (8) claimed that this process improved the thermal

stability of the palm oil.

A study by Francis Uchenna Ozioko (9) also shows the

possibility of producing bio – lubricant with soybean seeds

through solvent extraction process where it was observed that

insoluble gums were formed in the process.

The use of vegetable oils in diesel engines is nearly as old

as the diesel engine itself. The inventor of the diesel

engine, Rudolf Diesel, reportedly used groundnut (peanut) oil

as a fuel for demonstration purposes in 1900 (1). Some other

work was carried out on the use of vegetable oils in diesel

engines in the 1930's and 1940's. The fuel and energy crises

of the late 1970's and early 1980's as well as accompanying

concerns about the depletion of the world's non-renewable

resources provided the incentives to seek alternatives to

conventional, petroleum-based fuels. In this context,

vegetable oils as fuel for diesel engines were remembered.

They now occupy a prominent position in the development of

alternative fuels. Hundreds of scientific articles and various

other reports from around the world dealing with vegetable

oil-based alternative diesel fuels ("biodiesel") have appeared

in print. They have advanced from being purely experimental

fuels to initial stages of commercialization. Nevertheless,

various technical and economic aspects require further

improvement of these fuels. Numerous different vegetable oils

have been tested as biodiesel. Often the vegetable oils

investigated for their suitability as biodiesel are those

which occur abundantly in the country of testing. Therefore,

soybean oil is of primary interest as biodiesel source in the

United States while many European countries are concerned with

rapeseed oil, and countries with tropical climate prefer to

utilize coconut oil or palm oil. Other vegetable oils,

including sunflower, safflower, etc., have also been

investigated. Furthermore, other sources of biodiesel studied

include animal fats and used or waste cooking oils. Sources of

biodiesel with some emphasis on developing countries have been

discussed (2).

Several problems, however, have impaired the widespread use of

biodiesel. They are related to the economics and properties of

biodiesel. For example, neat vegetable oils reported to cause

engine deposits. Attempting to solve these problems by using

methyl esters causes operational problems at low temperatures.

Furthermore, problems related to combustion and emissions

remain to be solved. The problems associated with the use of

biodiesel are thus very complex and no satisfactory solution

has yet been achieved despite the efforts of many researchers

around the world. This article will briefly discuss economics

and regulatory issues as well as conventional diesel fuel

(petrodiesel) and then focus on research on the use of

biodiesel in a diesel engine.

The performance and emission behaviour of a spark ignition

engine run on groundnut oil blended lubricants was studied by

Ejilah I.R and Asere A.A (10) , where a benchmark test was

carried out on multigrade and monograde motor oil in

comparison with groundnut oil and result shows that groundnut

oil blended lubricants is slightly higher than multigrade oil

but comparable to monograde oil.

A.B Hassan , M.S. Abolarin , A. Nasir ,and U. Ratchel (11)

all worked on the investigation on the use of Palm Olein as

lubricating oil and observed that it exhibits a good base as

lubricant. They however recommended that different bleaching

agents other than the calcium hypochloride should be used.

Bleaching agents like activated carbon (charcoal) and acid

activated clay should be used as they are readily available

and cheaper.

A study on the friction characteristics of RBD Palm Olein in

comparison with paraffinic mineral oil using a Four – Ball

Tribotester was carried out by S. Syahrullail , J.Y. Wira ,

W.B. Wan Nik and W.N. Fawwaz (12) in which result shows that

RBD Palm Olein has a lower coefficient of friction than

additive – free paraffinic mineral oil.

Therefore, there has been major interest in the development

of many types of lubricants, including greases and hydraulic

fluids that are based on vegetable oils, such as a rapeseed

oil, castor oil and palm oil. These oils all have excellent

lubricating properties, load carrying capacities and corrosion

protection properties in comparison with mineral oil by A.R.

Lansdown (13).

2.1 CURRENT TRENDS ON VEGITABLE OIL BASED LUBRICANTS

Currently, vegetable oil-based lubricants have started to

replace the mineral-based oils for industrial lubrication.

This trend has occurred because mineral oil lubricants are not

readily biodegradable and are toxic. Global environmental

awareness has encouraged the production of environmentally-

friendly lubricants. The production and use of non-toxic,

biodegradable lubricants has become a major issue, especially

when the lubricant involved will come into contact with soil,

crops or ground water. Biodegradability is the ability of a

substance to be decomposed by the action of bacteria into CO2,

water and mineral compounds. There are several factors that

affect the biodegradability of a substance, including the

molecular structure, chemical properties and environmental

conditions [1]. Additional beneficial properties of vegetable

oil, such as a high viscosity index, good lubricity, high

flash point and low evaporative loss, have also made it

preferable for use instead of mineral oil-based lubricants

[2]. Therefore, there has been major interest in the

development of many types of lubricants, including greases and

hydraulic fluids, that are based on vegetable oils, such as a

rapeseed oil, castor oil and palm oil. These oils all have

excellent lubricating properties, load carrying capacities,

and corrosion protection properties in comparison with mineral

oil [3]. A few decades ago, large quantities of palm oil were

consumed by railway companies who used it almost exclusively

for greasing the axle boxes of the railway carriages [4]. Palm

oil has several advantages over mineral oil. Palm oil is

comparatively inexpensive, readily available, biodegradable,

environmental-friendly and renewable [5]. Furthermore, the

production of mineral based lubricants, such as those obtained

from petroleum, uses more energy and generates additional

pollution during the refinement process than the corresponding

process for vegetable oils.

Moreover Over the past decades, there has been an increase in

effort to reduce the reliance on petroleum fuels for energy

generation and transportation throughout the world. Among the

proposed alternative fuels, biodiesel and diesohol have

received much attention in recent years for diesel engines due

to their advantages as the renewable and domestically produced

energy resources. Moreover, the studies have shown that they

are environmentally friendly because there is substantial

reduction of unburned hydrocarbons, CO and particulate matter

emission when it is used in conventional diesel engine [3].

One of the interesting recent developments is a growing

realization that bioresources present practical alternatives

to fuels and lubricants derived from liquid fossil fuels.

About 30 years ago in Tanzania, locally pressed castor oil,

strained through an old sock was used as gearbox engine oil

[4]. This was no eccentricity was shown by the many tests

carried out on its uses as lubricating oil and its eventual

acceptance as a jet engine lubricant [4]. Biodiesel can be

produced from vegetable oils via transesterification process.

Nevertheless, biodiesel has been employed not only as an

alternative to the fossil derived fuels, but also as an

additive for diesohol - a blending of ethanol with regular

diesel. The globe includes Nigeria is presently facing two

major problems. Firstly, global warming must be reduced by

preventing the release of large amounts of carbon dioxide

which is created due to environmental pollution into the

atmosphere by searching for alternatives to existing

commercial petroleum based conventional fossil fuels and

secondly, the availability of existing fossil fuels can be

extended by adopting some scientific methodologies including

blending of conventional fossil fuels with economically

feasible, abundantly available, having renewable resources,

environmental friendly, and non conventional fuels. Time has

come to switch over from using non-renewable resources to

using renewable resources and switching will be imminent as

the present scenario of energy use is unsustainable. With

foreseen switchover, one will also be switching to the

sustainable energy base with no adverse impact on the

environment. Over the years, a little attention was paid to

the industrial use of palm oil. Nevertheless, recent studies

have indicated that apart from their domestic uses that they

can be used as engine lubricants, as replacement for biodiesel

if their properties are enhanced. Palm oil is gotten from the

palm fruit’s pulp. It is red in colour due to the presence of

beta carotene in it. Previously it was the second most widely

produced edible oil after Soya bean oil, 28 million metric

tons were produced worldwide in 2004 [1]. Palm oil is also

used in biodiesel production, as either a simply processed

palm oil mixed with petrol diesel or processed through

transesterification to create a palm oil methyl ester blend

which meets the international EN 14214 specification with

glycerine as a by product.

SoybeanProcessing:The soybeans undergo various processing in the course of their

preparation for oil extraction. Soybean seeds were purchased

from a local market at Bosso town, Minna, Niger State,

Nigeria. The seeds were selected according to their condition

where damaged seeds and some foreign materials were discarded

before seeds in good condition were cleaned thoroughly with

clean water, sun dried in the open, cracked and de-hulled. The

de-hulling was done by cracking the soybeans using mortar and

pestle and a separation of the hulls and cracked soybeans was

achieved using a tray to blow away the hulls in order to

achieve very high yield. The de-hulled soybeans were heated to

105°C for 35 min to coagulate the soy proteins to make the oil

extraction easier. The de-hulled and heated soybeans were

grounded into powder using a grinder prior to extraction in

order to weaken or rupture the cell walls to release soy fat.

Economics and Regulatory Issues On Diesel Fuel Derived

from Vegetable Oil.Economic reasons have been one of the major obstacles in

the use of biodiesel. Diesel fuel (DF) derived from vegetable

oils is more expensive than petroleum-based DF. The feedstock

for biodiesel is already more expensive than conventional DF.

For example, in the United States, a gallon of soybean oil

costs approximately two to three times as much as a gallon of

conventional DF. However, in the case of conversion of

vegetable oils or fats to their esters, the resulting glycerol

co-product, which has a potential market of its own, may

offset some of the costs.

In most European countries, however, transportation fuels

are so heavily taxed that tax incentives can be applied to

encourage the use of biodiesel in the form of lower or no

taxes on the biofuel and higher taxes on the petroleum-based

fuel (3,4). This subsidy artificially cheapens the biodiesel

to make it competitive. In many developing countries, the

overriding concern is to become independent of the imported

commodity petroleum. In the United States, the tax mechanism

is inapplicable because of the comparatively low taxes on

transportation fuels. Artificially regulating the demand for

fuels from specific sources by means of taxation is currently

politically not feasible.

Nevertheless, biodiesel is attractive for other reasons.

Besides being a renewable resource and therefore creating

independence from the imported commodity petroleum and not

depleting natural resources, health and environmental concerns

are the driving forces overriding the economic aspects in some

cases. These concerns are manifested in various regulatory

mandates of pollutants, particularly CAAA (Clean Air Act

Amendments of 1990) and EPACT (Energy Policy Act of 1992) in

the United States, which present opportunities for alternative

fuels such as biodiesel. A life-cyle analysis of biodiesel (5)

has shown that it is competitive with other alternative fuels

such as compressed natural gas (CNG) and methanol in the urban

transit bus market.

It is generally recognized that biodiesel has lower

emissions, with the exception of nitrogen oxides (NOx), than

conventional petroleum-based DF. For example, due to its lack

of sulfur, biodiesel does not cause SO2 emissions. The lower

emissions have caused biodiesel to be used in urban bus fleets

and to make it especially suitable for other niche markets

such as mining and marine engines. Besides environmental and

health reasons with accompanying Government regulations,

focusing on the use of biodiesel in niche markets is rendered

additionally attractive because not enough vegetable oil is

produced to supply the whole diesel market with biodiesel.

Numerous reports exist showing that fuel economies of certain

biodiesel blends and conventional DF are virtually identical.

In numerous on-the-road tests, primarily with urban bus

fleets, vehicles running on blends of biodiesel with

conventional DF (usually 80% conventional DF and 20%

biodiesel; for a list of most biodiesel demonstration programs

in the United States, see Ref. 6) required only about 2-5%

more of the blended fuel than of the conventional fuel.

Biodiesel. Definition of Biodiesel The term biodiesel has no unambiguous definition. It stands

for neat vegetable oils used as DF as well as neat methyl

esters prepared from vegetable oils or animal fats and blends

of conventional diesel fuel with vegetable oils or methyl

esters. With increasing emphasis on the use of esters as DF,

however, the term “biodiesel” increasingly refers to alkyl

esters of vegetable oils and animal fats and not the oils or

fats themselves. In an article on proposed ASTM standards,

biodiesel was defined (9) as “the mono alkyl esters of long

chain fatty acids derived from renewable lipid feedstock, such

as vegetable oils or animal fats, for use in compression

ignition (diesel) engines.” Nevertheless, clear distinction

between these different vegetable oil-based or -derived

alternative diesel fuels is necessary.

For use in the United States, the U.S. Department of Energy

has stated (10), “that biodiesel is already covered in the

statutory and proposed regulatory definitions of “alternative

fuel” which refer to any “fuel, other than alcohol, that is

derived from biological materials.” The Department, therefore,

is considering amending the proposed definition of

“alternative fuel” specifically to include neat biodiesel.”

The definition of biodiesel was not extended to include

biodiesel blends, with the Department of Energy stating that

“the issue of including biodiesel mixtures or blends comprised

of more than 20 percent biodiesel is currently under study.

However, this subject is complex and will require

significantly more data and information, and a separate,

future rulemaking, before DOE can make a determination as to

whether to include them in the definition of “alternative

fuel.”

Vegetable oils.

Most vegetable oils are triglycerides (TGs; triglyceride =

TG). Chemically, TGs are the triacylglyceryl esters of various

fatty acids with glycerol. For lubricant base oil use the

vegetable derived materials are preferred. Common ones include

high oleic canola oil, Castrol oil, palm oil, sunflower seed

oil and rapeseed oil from vegetable, and Tall oil from tree

sources. Many vegetable oils are often hydrolysed to yield the

acid which is subsequently combined selectively to form

specialist synthetic esters. Others naturally derived

lubricants include lanolin (wool grease, a natural water

repellent).

Whale oil was a historically important lubricant, with some

uses up to the latter part of the 20th century as a friction

modifier additive for automatic transmission fluid. (*)

In 2008, the biolubricant market was around 1% of UK lubricant

sales in a total lubricant market of 840,000 tonnes/year.

(**). Lanolin is a natural water repellent, derived from sheep

wool grease, and is an alternative to the more common petro-

chemical based lubricants. This lubricant is also a corrosion

inhibitor, protecting against rust, salts, and acids. Water

can also be used on its own, or as a major component in

combination with one of the other base oils. Commonly used in

engineering processes, such as milling and lathe turning.

Advantages of Using Vegetable Vegetable oils are considered as superior over petroleum oils

for producing lubricants because of some inherent properties it

possess. Petro-based production of lubricants involves

pollution generating process of petroleum extraction as well as

refinement while vegetable oils are made from renewable

resources. Vegetable oils also has the advantage of

biodegradability, low-toxicity and do not produce any harmful

effects on aquatic life. All these qualities carry significant

importance for applications in environmental-sensitive regions,

and situations where the danger of lubricants being

lost in the environment is higher. Plant-based lubricants also

ensure safety for the workers with low-toxicity, low volatile

organic compound (VOC) emissions and high flash point.

Vegetable oils also score higher than petroleum lubricants in

terms of viscosity index that allows vegetable oils to stay

thick even at higher temperatures. Vegetable-based oils also

enable reduction in friction in machinery components with the

presence of lubricity properties. Vegetable oil-based

lubricants also play an important role in

achieving rural economic development by ensuring better

livelihood for the farmers on the back of robust demand for

vegetable-based oils. Farmers are also benefited through joint

ownership in the companies that manufacture value-added

vegetable-oil products.

Vegetable oils, or their derivatives, are a good alternative to

petroleum oils as lubricants or lubricant additives in

environmentally sensitive industrial applications. In many

industries, around 40 percent of a lubricant can be lost to the

environment. With the petroleum prices at a record high,

development of economically feasible new industrial products

using soybean oil is highly desirable. Though soybean oil and

its derivative oleochemicals show superior lubricity,

vegetable-oil-based lubricants have a lower oxidative stability

and poor cold flow properties at low temperatures. One

potential way to improve oxidation and low-temperature property

is to modify it by attaching some functional groups at the site

of unsaturation.

Blending of the Ester

Blending conventional DF with esters (usually methyl

esters) of vegetable oils is presently the most common form of

biodiesel. The most common ratio is 80% conventional diesel

fuel and 20% vegetable oil ester (also termed “B20,” indicating

the 20% level of biodiesel; see also list of biodiesel

demonstration programs in Ref. 6). There have been numerous

reports that significant emission reductions are achieved with

these blends.

No engine problems were reported in larger-scale tests

with, for example, urban bus fleets running on B20. Fuel

economy was comparable to DF2, with the consumption of

biodiesel blend being only 2-5% higher than that of

conventional DF. Another advantage of biodiesel blends is the

simplicity of fuel preparation which only requires mixing of

the components.

Ester blends have been reported to be stable, for example,

a blend of 20% peanut oil with 80% DF did not separate at room

temperature over a period of 3 months (126). Stability was also

found for 50:50 blends of peanut oil with DF (43).

A few examples from the literature may illustrate the suitability

of blends of esters with conventional DF in terms of fuel

properties.

Total Loss Lubricants

Equipment such as boats, motorcycles, lawnmowers, chainsaw use

two-stroke engine oil. At the time of ignition of engine,

unburned or incompletely burn oil is directly lost in the

environment and causes harmful effects on water and aquatic

environment. Using BLC-220 and BLC-230  vegetable-based

lubricants can mitigate these threats with significantly lesser

degree of emissions from the equipment. Moreover, the released

fluid is non-toxic, biodegradable and enhances engine life.

Impact of Palm Oil Production

Palm oil production contributes significantly to economic

development in both Indonesia and Malaysia, providing a range

of benefits for both producers in the local economies and

consumers in global markets. These benefits include:

Income and Employment – Palm oil production provides direct

employment opportunities for millions of people in

Nigeria and elsewhere, and indirectly provides

livelihoods for countless others up and down the supply

chain. Many plantation owners are smallholders whose

profits remain within local communities.

Infrastructure Development - The expansion of the palm oil

industry has motivated the expansion of infrastructure in

formerly remote and poor areas of Nigeria and other

countries. The construction of roads, schools, hospitals,

telecommunications and other projects has helped spur

economic growth and given people access to formerly

unavailable services on a large scale.

Expansion of Food and Product Supply - Palm oil is widely used in

food products and cooking processes throughout the world,

providing affordable sustenance to hundreds of millions

of people globally. In addition to foods, palm oil is

also used in a range of consumer products, such as

cosmetics, soaps, detergents and biofuels.

Yet palm oil production comes at a cost to ecosystems and some

communities in the region. Specifically, rapid expansion of

palm oil plantations in recent decades has been linked to the

following challenges:

Deforestation/Habitat Loss - To make way for palm oil

plantations, vast tracts of forest and peatland have been

converted to agricultural land. This has led to habitat

loss for many endangered species, including “charismatic

species” such as the orangutan, the Sumatran tiger and

the proboscis monkey. Although it is possible to develop

oil palm plantations on “degraded land,” i.e. that has

already been cleared for agricultural purposes, some

developers prefer to clear virgin forest because it

contains timber that can be sold off for additional

profits. Nigeria has policies in place to protect virgin

forest and peatland from unbridled development, but

enforcement of these policies remains a challenge.

Regional Haze - Although outlawed in some countries,

controlled burning is often used to clear and manage land

for oil palm plantations, as well as to dispose of

plantation wastes. At certain times of the year, the

burning happens at a large scale and sometimes produces

uncontrolled forest fires, especially on highly flammable

peatlands, causing dangerous levels of haze to build up

in the atmosphere. In recent decades, the haze has

crossed national boundaries and become a region-wide

problem, straining relations between countries in

Southeast Asia.

Climate Change - The exact impact of palm oil cultivation on

greenhouse gas emissions and climate change is debated,

but some evidence suggests that the clearing of

rainforest and peatland, when combined with emissions

from industrial processes and economic development

related to the palm oil industry, is exacerbating global

climate change. The clearing of peatland, which is high

in carbon content, is considered especially problematic.

Since Southeast Asia is one of the most at-risk regions

for climate change in the world for the impacts of

climate change, the role of palm oil production in

climate change is especially germane.

Land Expropriation – Some palm oil producers are reported to

have engaged in corrupt and unethical conduct while

obtaining and developing land for palm oil plantations.

Local and indigenous peoples have in some cases been

subjected to human rights abuses, such as forced

evictions and illegal labor practices.

Other Industrial Pollutants - Palm oil processing produces large

amounts of effluents. When disposed of improperly, these

effluents can pollute waterways and cause hazards for

nearby humans and ecosystems. Additionally, palm oil

plantations sometimes make use of pesticides and

fertilizers. When used indiscriminately, these pesticides

and fertilizers can also pose threats to the environment.

Overall, palm oil production poses both opportunities and

threats to ecosystems and communities throughout the world.

The extent of those opportunities and threats is vigorously

debated, and since participants in the debate often invoke

conflicting scientific studies and different personal values

on environmental conservation and economic development, issues

surrounding palm oil development have defied resolution.

ISSUES IN LUBRICATION MARKET

Besides the performance issues of vegetable oils utilization

versus mineral oil based systems,

relative cost of the base fluids is always of concern. It is

believed that the approximate relative costs of the various

base fluids are:

Refined mineral oils - 1

Vegetable oils - 1.5 – 2

Synthetic esters - 4 - 12

One of the key needed oil property or characteristics that

vegetable oils lack in general are the

Following:

Oxidative instability

Poor low temperature properties

Perceived poor hydrolytic stability

Fluidity of oil is mainly determined by the efficiency of

molecular packing, intermolecular interactions, and molecular

weight. Saturates have too high a level of crystalline

symmetry, which facilitates interlocking of the sharp needle-

like triacyglyercol crystals as temperature decreases.

Vegetable oils and their double bonds influence low

temperature behavior. The FAC of most of the vegetable oils

that are readily available and inexpensive are not suitable

for lubrication due to their high saturates or polyunsaturates

fatty acid content. Monounsaturated fatty acid oil present

optimum oxidative stability and lower temperature properties.

As a consequence, vegetable oils that have high stability and

low pour points can be produced by converting all the fatty

acids into a monounsaturated fatty acid. Thus, base fluids for

lubricants must have a balance of fatty acids, preferably a

high level of monounsaturated, minimal polyunsaturates, and

ideally no saturarates at all for cold climates. The following

data below gives an example of the aforementioned properties

of vegetable oils as compared to mineral oils. Unlike most

mineral oils, vegetable oils display very high viscosity

indices (VI). This is a relative measurement in change of base

fluid viscosity between 40°C and 100°C and indicates the

change in viscosity over an extended temperature range.

Vegetable oils afford higher flash points as compared to

mineral oils. In terms of pour point, vegetable oils are

comparable to mineral oils except for one point. Mineral oils

are more responsive to pour point depressants additives and

give pour points of -30°C to -50°C. Vegetable oils are not as

responsive to conventional pour point depressants since the

conventional pour point depressant have been developed for the

paraffin waxes found in mineral oils versus the traditional

waxes found in most vegetable oils.

However, one should not need to worry about the shortcomings

of vegetable oils for lubrication. Mineral oil fluids, like

vegetable oils, cannot meet most lubrication performance needs

without additives. Available additives that enhance base

fluids are:

Antioxidants

Detergents

Dispersants

Viscosity Modifiers

Pour Point depressant

Antiwear agents

Rust and corrosion inhibitors

Demulsifiers

Foam inhibitors

Thickeners

Friction Modifiers

Other additive e.g., dyes, biocides, etc.

ESSENTIAL QUALITIES OF A GOOD LUBRICANT

To reduce the frictional losses between metal to metal rubbing

or sliding parts, lubrication is required. Below are the some

essential qualities of a good engineering lubricant.

01) VISCOSITY: – When any lubricant offered resistance to the

deforming forces, it is called viscosity of the lubricant.

Good quality lubrication oil must maintain sufficient

viscosity at higher temperatures and it should not be too

viscous at lower temperatures.

For high speeds, low viscosity lubricants are suggested while

for large clearance and high loads; high viscosity lubrication

oil is recommended. The viscosity of oil increases, if the

temperature of mating surfaces decreases.

02) FLASH & FIRE POINT: – Flash point of the lubrication oil

is the minimum temperature at which it gives off enough vapour

to form a momentary flash when naked flame is brought near its

surface, while the fire point is the lowest temperature of the

lubrication oil, where it burns continuously. To avoid the

possibility of fire, the flash point of oil must be higher

than the temperatures likely to be developed in the rubbing

surfaces.

The fire point is generally higher than the flash point and

the difference between flash point and fire point must be 18

degree centigrade at higher side.

03) OILINESS: – It is the property of lubrication oil to

spread and attach itself firmly to the lubricating surfaces.

When mating surfaces are subjected to a high intensity of

pressure, it is recommended to particularly high oiliness; so

that the metal is protected by a layer of oil and the wear is

reduced.

04) VOLATILITY: – Lubrication oil losses a certain weight due

to evaporation when it is subjected to high temperature for

long hours. This loss is known as “loss by evaporation”. The

consumption of oil is considerably increased with high

volatility at normal working temperatures that is why low

volatility is always suggested for lubrication oil.

05) STABILITY & INSOLUBLE RESIDUE: – Stability of oil is to

resist oxidation that would yield acids and sludge. Good

lubrication oil must have high stability.

Free carbon or hydrocarbons decomposing into carbon at high

temperature is called as insoluble residue. Good quality

lubrication oil should not have any insoluble residue.

In Limited, an authorised Shell Lubricant distributor is found

in Nigeria, they offer a complete range of automotive,

industrial lubricants and industrial chemicals.

Lubricant Testing: Evaluating Tribological Behavior of lubricating oils and greases

Lubricants form an important part of most mechanical systems.

The right lubricant can enhance system life, enhance

efficiency, cool and remove debris. Lubrication is an

interesting and an innovative field where the choice of an

appropriate lubricating media is made based on the

application. The term lubricant brings to mind oils and

greases. These are the most popular lubricating media in use

currently. However, many applications now use solid lubricants

like Graphite, Molybdenum Di Sulfide (MoS2), Boron Nitride and

Polytetrafluroethylene (PTFE) where use of oils and greases is

not desirable.

Coming back to the lubricating oils and greases – oils

typically comprise of “Base Oil” and “Additives”. Additives

are added to base oil to give the lubricating oil its end

performance characteristics. Similarly, greases also use

additives to achieve the desired performance characteristics.

It is important to evaluate these additives themselves as well

as the end product to verify how well the lubricant does its

job. To aid development and quality check, there are a variety

of tribological tests for lubricants in the market. Some

popular tribometers for lubrication evaluation are:

Four Ball Tester:This is an excellent development and quality

check method. The unique sample configuration of three bottom

balls and one top ball makes a very stable and a repeatable

contact allowing tests to be very repeatable.  It can be used

to determine Wear Preventive properties (WP), Extreme Pressure

properties (EP) and friction behavior of lubricants. The

drawback of the Four Ball Tester is that its contact geometry

creates a point contact – this is great to create a very

repeatable test geometry, but a point contact is usually not

encountered in real life applications. However, the wide

acceptance of its test results make it an excellent choice to

benchmark products. It is a good choice for R&D due to its

relatively inexpensive samples and quick results. Its can be a

great marketing tool for lubricant manufacturers wanting to

showcase lube performance as its tests are widely accepted.

“Timken” OK Load Tester: This tribometer is a great tool for

lube testing. It was originally developed Timken and was used

to determine the load carrying capacity of lubricants. It uses

a bearing race pressed against a steel block creating a line

contact. This line contact is a lot more representative of

real life contacts when compared to the point contact as in

the Four Ball Tester. The Timken “OK” Load test requires the

test load to be increased until the lubricating film between

the ring and the block is broken. Scoring is observed as a

result of this broken lubricant film and this load value is

then reported as the Timken OK Load. This tribometer is a good

choice for R&D and quality control. Easily available samples

and quick set up make it a good choice for lubricant

evaluation.

Many researchers (Masjuki and Maleque (8); Yunus, et al.

(14); Waleska, et al. (15)) have been using various vegetable

– based oil lubricants and additive, but there are limited

references to the possibility of combining two vegetable based

lubricant together. The present research focus on

investigating the lubricating properties of a mixture of palm

steerin and palm olein as lubricant using a locally machined

tribotester.

CHAPTER THREE

3.0 METHODOLOGY

3.1 MATERIALS

The test materials that will be used in the experiment

shall include chrome alloy steel, aluminium and cast

iron. The test materials shall be of equal sizes, and

well polished. At the start of each new test, the

material will be well cleaned before commencing each

experiment. A machined tribotester will be required to

carry out the test.

LUBRICANTS.

The lubricants needed for this experiment were RBD palm

steerin together with palm olein and paraffinic mineral

oil. The paraffinic mineral oil will be compared with the

palm steerin and palm olein mixture. The volume of the

lubricant used will be 10mL for each test lubricant. The

density of the mixture and that of paraffinic mineral oil

shall also be determined.

3.2 METHOD

In these experiments, the test temperatures, which were

expected to influence the friction and wear

characteristics of lubricants, were evaluated. The

experiment will be carried out for 1hr under a 392.4 N

load and with a spindle speed (rotational speed) of 1200

rpm. The three bottom materials in the tribotester will

be evaluated for wear and the average diameter of the

circular scar formed from rotation will also be measured.

The lubricating ability of the vegetable based oil

mixture will be evaluated based on the frictional torque

produced in comparison with the paraffinic mineral oil.

Prior to the experiments, all parts in the tribotester

(test material and the oil cup) shall be cleaned and

wiped so that no traces of solvent remain when the

materials are assembled or when the lubricant is

introduced. The materials in the oil cup assembly will be

well placed in such a way that it will be static during

the experiment. The upper spinning ball will be well

locked and tightened into a spindle. The test lubricant

shall be confirmed to have filled all the voids in the

test cup assembly. To avoid shock, the test load shall be

applied slowly as the lubricant is heated to the desired

temperature. As the test temperature is reached, the

drive motor, which was set to drive the top ball at the

desired speed, will start. After the 1hr test period, the

heater will be turned off and the oil cup removed from

the machine. The scar area will then seen when the oil

attached is wiped by tissue. The material will finally be

taking to a microscope for further evaluation. The

diagram of the setup is shown below.

FIG. A SCHEMATIC REPRESENTATION OF A

TRIBOTESTER.

1 –stationary ball 2 – Rotating single ball 3 – Rotating

gripper for upper ball 4 – Test lubricant 5 – Cup for griping

stationary three balls 6-lock nut 7-balls ring 8-thermocouple

REFERENCES.

1 Ilija Gawrilow, “palm Oil Usage in Lubricants”, 3rd

Global Oil and Fats Business Forum U.S.A., October 8,

2003.

2 Michel Roegiers, Hongli Zhang, Boris Zhmud, (2008),

“Elektrionized Vegetable Oils as Lubricity Components

in metalworking Lubricants”, Vol. 36, No 3,p133.

3 Will Greene, (2013), “Palm Oil in Indonesia and

Malaysia: A Controversial Industry”, FigerMine

Research.

4 Komiya H. “The Present Condition and the Technical

Trend of Natural Decomposition of Vegetable Oil and Fat

Grease”. The tribology 2005; 216(8):28-30

5 Nosonovsky, M. (2000), “Oil as a Lubricant in the

Ancient Middle East”, Tribology Online, 2(2); pp 44 –

49.

6 Alla, M.P. and Richard, J.A. (2004), “Oxidation

Stability and Tribological Behaviour of Vegetable Oil

Hydraulic Fluids”, Tribology Transactions, 47(2), pp182

– 187.

7 Kalin, M. And Vizintin, J. (2006), “A Comparison of the

Tribology Behaviour of Steel/Steel, Steel/DLC and

DLC/DLC Contact when Lubricated with Mineral and

Biodegradable Oil”, Wear, 261, pp 22 – 31.

8 Masjuki, H.H and Maleque, M.A. (1997), “Investigation

of the Anti – Wear Characteristics of Palm Oil Methyl

Ester Using a Four – Ball Tribotester Test”, Wear, 206,

pp 179 – 186.

9 Francis Uchenna Ozioko (2012), “ Extraction and

Characterization of Soybean Oil based Bio Lubricant”,

Journal on Tribology, AU J.T. 15(4): 260 – 264.

10 Ejilah I.R. and Asere A.A. (2008), “ A Comparative

Performance and Emission Analysis of Groundnut Oil and

Mineral Oil Based Lubricants Using a Spark Ignition

Engine”, Agricultural Engineering International: The

CIGR E Jornal Manuscript EE 07017. Vol. X.

11 A.B. Hassan, M.S. Abolarin, A. Nasir and U. Ratchel.

(2013), “ Investigation on the Use of Palm Olein as

Lubrication Oil”, Federal University of Technology,

Minna, Nigeria.

12 S. Syahrullail, J.Y. Wira, W.B. Wan Nik and W.N.Fawwaz.

(2013), “Friction Characteristics of RBD Palm Olein

Using Four – Ball Tribotester”, Applied Mechanics and

Materials, Vol.315, pp936 -940.

13 A.R. Lansdown, (2004),“Lubrication and Lubricant

Selection”, Professional Engineering Publishing

Limited, United Kingdom.

14 Yunus, R., Ahmadun, F., Tian, E.I., and Perez, J.M.

(2004), “Lubrication Properties of Trimethylolpropane

Ester Based on Palm Oil and Palm Kernel Oils”, European

Journal of Lipid science and Technology, 106, pp 52 –

60.

15 Waleska, C., Perez, J.M., Sevim, Z.E., and Filomena, C.

(2006), “A Study of the Oxidation and Wear Properties

of Vegetable Oils: Soybean Oil without Additives”,

Journal of the American Oil Chemist Society, 83 (1), pp

47 – 52.