In 1990, Eduard Eddy Stempfel of the Swiss specialty lubricants company Aseol AG was brimming with enthusiasm for biodegradable lubricants. Traveling to Denver that October to address the National Lubricating Grease Institute, the chemical engineer and grease expert predicted the time was ripe for broad acceptance of these products.
Looking back almost 25 years later, the time is still ripe, he believes. There are more and better base fluids and additives to choose from, biodegradable products are easier to formulate and manufacture, reliable tests are in place to demonstrate performance, and labeling and purchasing policies have raised public awareness. Even OEMs have opened their doors, as their performance needs are met.
Yet, as Stempfel concedes, there remain a sizeable void where willing buyers should be and a price gap that disfavors biolubes. Few applications have emerged to join the early ones he cited in 1990, such as two-stroke engine oils, railroad flange lubricants, mold-release agents, wire rope lubes, construction excavators and other hydraulic equipment used near water, food processing, agriculture, and water purification plants. But on the plus side, after two decades of spadework the seeds of wider success are now in place, he told this years meeting of the European Lubricating Grease Institute in Amsterdam.
Still based in Bern, Switzerland, Stempfel is now global product manager for food grade lubricants at Fuchs Lubritech, which acquired Aseol from Shell Lubricants in 2010. At the ELGI meeting he pointed to a number of areas where progress has been made – and others where the biodegradable lubes market still lags.
For one thing, we expected to see more pressure from legislative bodies to push biodegradable products, Stempfel remarked. We didnt see this, and theres still no global legislation. Those bodies who do regulate it, only do so locally.
In some cases, biodegradable lubes still havent found the right niche. Food and agricultural machinery, for example, have not proved an ideal fit after all. Today its possible to use them, but it may not make sense. Food processing and agriculture imply humidity and bacteria, so from a hygienic point of view, biodegradability is still a question mark. Plus, theres competition from other food grade products with better performance.
Everyone back then spoke of having biodegradable greases, it was a sort of hype. But only one test for biodegradability was available, and it was not really for grease, Stempfel continued. That was the old CEC-L-33 test method, created in 1982 and updated in 1993, which actually was intended to measure biodegradability of two-stroke oils in water. It only provided a measure of primary degradation, and was never designed for use on greases.
Biodegradability is still important, but at last now its defined by OECD methods for testing biodegradability that allow much better assessments, Stempfel said. There also are more specific product requirements, such as ecotoxicity, renewability, OEM approvals and energy-saving potential.
The early days also had no labels to identify biodegradable lubricants. Since then, labeling schemes have been developed, so in the European Union we have the ecolabel Marguerite, plus you have labels from Environment Canada, the Nordic Swan ecolabel, the Blue Angel in Germany and others. The U.S. Department of Agricultures BioPreferred Program also is nudging purchases of biobased lubricants that boast high levels of renewable content.
Turning to look at the ingredients available for biodegradable greases, Stempfel said, Regarding base fluids, there is a much bigger variety of different types available today, especially in the range of synthetic esters – saturated and unsaturated – and specially treated vegetable oils. A big step forward is that todays chemists can usually get complete data sets of raw materials, consisting of biodegradability, renewability and toxicity.
The slate of suitable additives, quite limited before, also has blossomed. Additive manufacturers recognized the lack, and its not a problem now to get products and even to get the eco-label, he said. Not only is the variety of additives greatly expanded, but the EU has published a helpful Lubricant Substance Classification list, nicknamed LuSC, to assist formulators in their selection. It lists ingredient options by both substance type and brand name, so today one can chose from a big variety of additives which fulfill all relevant environmentally regulated requirements. The LuSC document is kept updated in the Product groups and criteria area at http://ec.europa.eu/environment/ ecolabel/eu-ecolabel-for-businesses.htm.
Meanwhile, grease manufacturing processes are not much changed, with open kettles, Contactors and reactors still used for making biodegradable greases, Stempfel continued. But one interesting point is the use of microwaves for making biodegradable grease, invented by Lou Honary of the University of Northern Iowa. Microwaving appears to be particularly well-suited to making greases from biobased materials.
With the varied ingredients now available, its much easier today to formulate high-performing biodegradable lubricants and greases, and these are winning converts in the field. One example is the tunnel-boring machines that cut a six-kilometer section of the Bern-to-Zurich route, using a biodegradable hydraulic fluid with excellent results. That success led the equipment manufacturer and operator to adopt biodegradable greases, too. The offshore wind power industry could be next, Stempfel suggested.
Even with the buying public more aware now of biodegradable greases, the price-to-performance ratio remains a stumbling block, he added. Regarding the global marketplace, the European Union members still seem to be the most advanced, although the market in the United States has made progress as well.
Biodegradability as a single argument has disappeared, and you also need to have technical performance. If you dont look at performance first, you will get it wrong, he asserted. Todays list of expectations for environmental products now include life-cycle analysis, renewability, CO2 reduction, energy savings and more.
But one particular thing has been slow to change: In the 90s, many biodegradable products were tagged with the empty phrase environmentally friendly. In Denver, Stempfel and his Aseol coauthor Lucia Schmid had urged the grease industry to supress this term and to use verbiage like imposes less strain on the environment. That struggle continues, he admits. Nothing is environmentally friendly, but we still see a lot of products claiming to be eco-friendly. Maybe this misleading argument will finally disappear in the next 20 years, he said at the April ELGI meeting.
Eco-lubricant products have become a full and accepted part of the lube family. Theyre not exotic or strange any more, Stempfel said in closing. For the sake of the environment, I hope well see more adoption of them in the next 20 to 25 years.