"The objective of this research was to develop a product that could be used as a lubricating grease but that was made only from natural materials and was therefore 100% biodegradable", José María Franco, a chemical engineer at the University of Huelva and co-author of the study published recently in Green Chemistry, tells SINC.
Environmentally-friendly greases are "oleogels" that use cellulose derivatives from plants and ricin oil (from a bush in the Euphorbiaceae family) as a lubricant base. Franco says these new formulations are "an alternative to traditional lubricating greases, which create pollution that is difficult to combat once discharged into the environment".
Lubricants used in industry are made from non-biodegradable components, such as synthetic oils or petroleum derivatives, and thickeners made with metallic soaps or polyurea derivatives (a family of synthetic polymers). These are currently the best performers, but they also imply more problems from an environmental perspective.
Millions of tonnes of hydraulic and industrial oils, and others from machinery, are discharged each year into rivers, the sea and fields. Mineral-based oils can contaminate groundwater for more than 100 years, and can prevent the growth of trees and prove toxic to aquatic life.
Only partial solutions have been found to date for this problem, such as substituting mineral oil for vegetable ones, but no alternatives had been found to the metallic thickeners, which are also highly polluting. The new green grease provides an answer, although the scientists admit that "more research is needed" in order to perfect its lubricating and anti-wear performance.
Franco tells SINC that the new material "has a similar level of mechanical stability to that of traditional greases, and it is highly temperature resistant, with rheological properties (viscosity) that do not change greatly, although we have observed that the material is expelled in large quantities when subjected to large inertial forces at high temperatures". When this substance is used in bearings, it is important that it is not easily shed. This will reduce the lubrication frequency, thus maintaining the ideal functioning conditions for machinery for a longer time.
The researchers will continue to investigate this aspect in order to find a way of balancing the use of biodegradable ingredients to manufacture the grease while also optimising its lubricating capacity.
In any case, the scientists have proved that "oleogels" based on cellulose derivatives are not only environmentally friendly, but are also advantageous in that they are easier to process, and that manufacturing them requires simpler technology than that used to make conventional greases.
R. Sánchez, J. M. Franco, M. A. Delgado, C. Valencia y C. Gallegos. "Development of new green lubricating grease formulations based on cellulosic derivatives and castor oil". Green Chemistry 11: 686-693, 2009.
SINC | EurekAlert!
A Map of the Cell’s Power Station
18.08.2017 | Albert-Ludwigs-Universität Freiburg im Breisgau
On the way to developing a new active ingredient against chronic infections
18.08.2017 | Deutsches Zentrum für Infektionsforschung
Whether you call it effervescent, fizzy, or sparkling, carbonated water is making a comeback as a beverage. Aside from quenching thirst, researchers at the University of Illinois at Urbana-Champaign have discovered a new use for these "bubbly" concoctions that will have major impact on the manufacturer of the world's thinnest, flattest, and one most useful materials -- graphene.
As graphene's popularity grows as an advanced "wonder" material, the speed and quality at which it can be manufactured will be paramount. With that in mind,...
Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.
Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...
For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.
While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...
An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.
The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...
A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.
Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...
16.08.2017 | Event News
04.08.2017 | Event News
26.07.2017 | Event News
18.08.2017 | Life Sciences
18.08.2017 | Physics and Astronomy
18.08.2017 | Materials Sciences