Figure 3. Project aims to replace toxic solvent used in making Li-ion batteries and improve their performance and life. Source: Solvay.
"We are using similar technology at others plants in Ontario, here in Midland and Pittsburgh. It's a great technology because it's less invasive and able to treat a lot of remediation issues while they are in place rather than having to dig up soil and remove it for treatment. Effectively you are replacing the pumps and treatment systems such as scrubbers and distillation columns that have traditionally done this sort of job," explains Mark Weick, director of sustainability."Although the target at Terneuzen was dioxane, we are continuously working to find the best possible species to conduct phytoremediation. Our efforts to utilize existing species like poplar and willow trees have been successful. The suite of contaminants often varies from site to site and [we] will look to other indigenous species when we have unique issues that need to be addressed," he adds.Dow is relying on phytoremediation at a former manufacturing site in Sarnia, Ontario. "We didn't want to have to run lots of infrastructure once we had left, so we have almost 1,000 trees — poplars and willows — doing a wonderful job. We continue to review data in terms of cost benefit analysis. We have set operations and maintenance procedures — the trees are evaluated on a regular basis (normally at least once per year) and replaced as needed."The company's latest initiative is in Houston. Here, Dow is collaborating with The Nature Conservancy, Austin, Texas, on the use of trees to replace gray infrastructure such as scrubbers. "No one considered reforestation an economically viable option to gray infrastructure before. Right now we are publishing the work in an academic journal and discussing the technology — benefits and questions — with the appropriate regulatory officials."The challenge now for Dow is proving that the tree technology works in a structured way. "After all, we as site owners are accountable to the regulators to ensure that remediation is taking place to the appropriate standard. But such green infrastructure solutions are less proven than the traditional pipes and pumps," Weick notes.MORE SUSTAINABLE PRODUCTION
Using renewable resources and advanced sustainable manufacturing processes is drawing more attention, too. For instance, Elevance Renewable Sciences Inc.
, Woodridge, Ill., is doing both to create new products and ingredients that deliver enhanced performance.Called Renewicals, the products are created via an olefin methathesis catalytic process that breaks complex molecules into simple fragments and recombines them in novel ways, for example to create polymers or to exchange functional groups."Combined with patented processing technology, natural oil compounds from soy, canola and palm are synthesized with greater efficiency, offering superior performance at a lower cost and using less energy to produce than fossil-based products," says Andy Shafer, executive vice president, sales and market development. Any renewable oil is a potential feedstock; emerging ones such as from jatropha and algae already are being evaluated.Product options so far include waxes, renewable alpha olefins, unsaturated acids and esters, as well as derivatives of the unsaturated acids and esters, such as diacids, epoxides, novel lubricant base stocks, surfactants and alcohols.Elevance has a joint development agreement with Stepan Co.
, Northfield, Ill., which in late March launched the first product resulting from the cooperation — Steposol MET-10U, a novel surfactant derived from natural oils that is targeted to displace solvents.Elevance itself in February announced expanded availability of Aria WTP (wide temperature performance) 40 base stock, which is made via proprietary technology from renewable feedstocks. "We expect to see Aria WTP 40 in gear and hydraulic fluid lubricant formulations within the year," notes Shafer.Also in February, Elevance revealed that it is partnering with Versalis, the chemical subsidiary of Eni, Milan, Italy, to jointly develop and scale new metathesis technology to produce chemicals from vegetable oils."Today we use a metathetic catalyst based on ruthenium. Being able to use molybdenum and tungsten would allow us to deploy our technology at, for example, ethylene plants. There are plenty of these that need repurposing in Europe, for example," he explains.MORE BENIGN BATTERY PRODUCTION
Meanwhile, Solvay Specialty Polymers, Bollate, Italy, has launched the Life+ Glee project, a highly focused sustainability program that aims to use water instead of organic solvents in manufacturing rechargeable lithium ion (Li-ion) batteries.At the moment, the Li-ion slurry production process uses the solvent N-methyl-2-pyrrolidone (NMP), which is classified as a "substance of high concern" by the European Chemicals Agency; REACH regulations call for its progressive substitution by more sustainable chemicals. Unfortunately, replacing the toxic solvent with water would expose cathode active materials (CAMs) to corrosion.So the project is seeking to develop waterproof yet Li-ion-permeable barrier technologies for the CAMs. "The novelty is not so much in the material we are using — a thin layer of metal/metal oxide — but the technology used to apply it. The protective layer has to be thick enough to protect from water yet thin enough to let the lithium ions work," says Francesco Triulzi, alternative energy open innovation manager. "In addition, the existing solvent recovery and re-purification phase is very costly and difficult because of the associated health and safety risks."Solvay
is nearing the end of the design phase for a pilot plant to produce the new materials at its research and innovation center in Bollate. The company is targeting March 30, 2015 as the date for the first materials to be sent for testing by battery makers, research organizations and electric car manufacturers.The Life+ Glee project should result in a chemicals plant capable of producing several hundred kilograms of active battery cathode material per year under real industrial conditions."These are very small volumes in comparison to a commercial plant which would produce one hundred or one thousand times this amount. However, one key goal of the Life+ Glee project is the evaluation of the large-scale industrialization and commercialization potential of the technology," adds Triulzi.Solvay is providing €1.7 million ($2.3 million) in funding, and the European Union is kicking in €593,000 ($818,000).