Biolubricants and Bio Lubes
Biolubricants and Bio Lubes
Biolubricants are made from vegetable and plant oils, which themselves are a type of non-food biomass energy. Our planet is highly dependent on the use and consumption of fossil fuels (e.g. petroleum, coal and natural gas) to fulfil its energy needs. Clearly, our petroleum based economy can not be sustained indefinitely relying solely on cheap and non-renewable fossil based oils and materials for its energy needs.
Alternatives to petrol, diesel and other forms of fossil fuels have already been implemented in a variety of biomass based transportation fuels such as biodiesel and bioethanol. Biofuels derived from sugar cane and oil crops for transportation which where non-existent only a few decades ago are now becoming common place with advanced biofuel pumps being installed in filling stations around the world. Then it only makes sense that as well as filling our vehicles with biofuels we should also fill them up with “Biolubricants”.
Lubricants, or “Lubes” for short, are liquids and grease solids that are used to improve the ease of movement between two mating surfaces. Lubricants reduce friction, overheating, mechanical wear and the corrosion of metallic and moving parts. Most lubricants used today consist of over 70% of a petroleum based oils plus a mixture of additives and chemicals that modify the natural properties of the base oil(s) to meet a designed requirement.
Most of the worlds consumption of oils and lubricants are used in products such as engine oils, gearbox oils, transmission and hydraulic fluids, as well as general industrial oils and greases with the vast majority of these still being based on mineral oils.
Today global concerns over the environmental pollution caused by many fossil fuel based lubricants, have created a growing worldwide trend of promoting new environmentally friendly bio based lubricants and other such renewable and biodegradable lubricants.
Biolubricants is the term used mainly to refer to liquid oils derived from renewable or biomass feed stocks. Biolubricants are formed by heating the biomass feedstock in the absence of oxygen, called Pyrolysis, or partially combusted in a limited oxygen supply, to produce an oil-like liquid. This bio crude oil is further refined into various other biolubricant and bio oil based products.
But there are some technical problems to be overcome associated with this conversion process as the acidic value and water content of the resulting bio crude oil is high, plus energy (possibly fossil fuel energy) has to be consumed in its production.
Plant and vegetable oils on the other hand are composed mainly of different natural oils, fats and acids making them biodegradable and non-toxic. Even though these natural oils can have excellent lubricity without the need for additional additives and come in a range of viscosities. However, the properties of some types of vegetable oils such as low melting points and oxidative stability can limit their use as a biolubricant.
Historically agricultural land was only used for food production, but today agriculture and farming activities now include to growing of crops for non-food applications regardless if they are edible or non-edible products. Such crops include vegetable oils, wax ester oils, plant oils and carbohydrate based biolubricants along with rape seed, sunflower and olive oils are all finding industrial applications with vegetable oils being a major source for biolubricant production.
The substitution of fossil fuels and mineral oils with a newer biodegradable lubricant based oil can help to significantly reduce the environmental impact and pollution. Vegetable and sunflower oils have been used as a form of lubrication of machinery and in the massaging properties of the human skin for thousands of years as they have the advantage over mineral-based oils in being biodegradable and non-toxic. Other types of renewable non-toxic resources include wild plants, bio-genetic materials and animal products, residues and wastes that originate from
agricultural and even forestry production.
Vegetable oils have a large number of other inherent positive qualities that give them an advantage over conventional petroleum oils as the feedstock for biolubricants. Some of the qualities of vegetable oils such as excellent biodegradability and low ecotoxicity, are particularly important for oils and lubricants used in environmentally sensitive areas. For example in river or marine ecosystems, or for those activities in which there is a high potential of the lubricant being lost or spilled to the surrounding environment.
Some advantages of plant oil based products for biolubricant production include:
- Good viscosity
- Low friction coefficients
- Excellent lubricating properties
- Environmentally friendly, renewable and biodegradable
- Low ecotoxicity, non-water polluting
- Improved fuel economy and reduced engine emissions
- Low cost production and minimal disposal expenses
In spite of these advantages, there are a few limitations or disadvantages of these natural oil products too:
- Operating temperature limitations
- Low flash point and potential fire hazard
- Quick ageing and degradation of bio oils
- Lack of viscosity range
- Poor low temperature fluidity during winter months
- Compatibility with existing oil seal and gasket materials
- Easy formation of sludge resulting in filter clogging and increased maintenance
While there are many advantages and disadvantages to biolubricants, chemistry has played an important role in the transformation of the raw biomass material into a usable lubricant. The production of biolubricants from green biomass feed stocks is different to that of conventional lubricants made from mineral oil. While all forms of lubricants are formulated from one or more types of base fluid, they also have property enhancing chemicals, commonly called additives, added to or blended with them to improve their physical properties.
The actual percentage of additives added to a particular formulation differs greatly depending upon its application ranging from hundreds of parts-per-million (ppm) for antifoaming agents and biocides, through to 1% in simple oils and up to 40% in metalworking fluids and gearbox lubricants. On average, most commercially available lubricating oils consist of about 90% base oil(s) and 10% additives to help improve flow, lubricity, ageing, and anti-wear.
Today, market demands and development for biolubricants and transportation fuels has increased environmental compatibility, reduced harmful emissions, improved performance (including longer lifetime and engine efficiency) but above all, reduced our dependence on fossil fuel energy. The depletion of the world’s crude oil reserves, ever increasing oil prices, and issues relating to the conservation of energy have brought about a strong and renewed interest in the use of bio-based oils and fluids.
This renewed interest in vegetable oil as a bio-based lubricant has increased as environmental awareness has increased. The harmful effects of petroleum oils on environmental and human health are becoming ever more obvious. While a the same time, high performance and cheaper vegetable oil based biolubricants have been developed and marketed. The emphasis on the development of renewable, biodegradable, and environmentally friendly industrial fluids, such as biolubricants, has lead to the increasing use of natural fats and oils for non-edible industrial purposes.
However, in order for “biolubricants” to be successful and mainstream, the chemical industry must also take notice of these important developments and consumer needs. Chemistry plays an essential role in providing solutions for society’s problems and the progressive change over of the chemical industry to renewable and sustainable feed stocks (food, water, energy, raw material feed stocks) is an inevitable necessity.
Bio based lubricants and products have the ability to dramatically alter our world for the better. Improving biomass technologies will largely help to decentralise our fuel and chemical production, reduce the release of harmful gases into the atmosphere, and will reduce the dependence on oil imports and in many countries bio-based products are now being recognised as critical to the economy, environment and even national security.
The world’s era of low cost oils and lubricants has finished. Biodegradable oils and other eco-friendly lubricants are now moving into a more competitive and mainstream position due to rising oil prices, limited supplies of natural resources, global climatic change and increased environmental sensitivity. As a result various alternatives to petroleum based lubricants are now being explored.
The current emphasis on conservation has resulted in renewed interest in the use of modified natural oils for non-edible, automotive and industrial purposes. The last few decades there has been important progress towards the use of biodegradable lubes and greases from renewable sources. Today, biolubricants help lubricate the world the natural way.