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Volume 92 Issue 26 | pp. 24-28
Issue Date: June 30, 2014 | Web Date: June 26, 2014

Seeing The Green Side Of Innovation

Green Chemistry & Engineering Conference focuses on translating use-inspired basic research into sustainable products
Department: Science & Technology | Collection: Entrepreneurs, Green Chemistry, Sustainability
News Channels: Environmental SCENE, Organic SCENE, Materials SCENE
Keywords: green chemistry, open innovation, life-cycle analysis, dyeing, quantum dots, recycling

Jump to Topics:
- Green Chemistry Gets A Boost From Open Innovation Platforms
- Green Business Plan Competition Fosters Innovation
- Natural Biocide Offers An Alternative For Fracking
- Sigma-Aldrich Develops Green Cross-Coupling Reaction Kits
- EMD Millipore Makes Progress In Biopharma Plastics Recycling

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Nike, BASF, Hewlett-Packard, the National Aeronautics & Space Administration, Eastman Chemical, United Soybean Board, Pfizer, the Environmental Protection Agency, Bayer MaterialScience, Codexis, Johnson & Johnson, Amgen, DuPont, World Wildlife Fund. Most chemists will recognize the names on this eclectic list. But if any were to venture a guess at what ties this selection together, green chemistry might not be the first thing that pops into mind.

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Credit: Nike
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Credit: Nike

From being the makers of medicines, transportation fuels, plywood, running shoes, food, televisions, shampoo, and much more, the members of this list and others like them—large and small—have a stake in developing greener and more sustainable chemical products and processes. For example, sportswear giant Nike just launched a line of clothing in which the fabric is made using polyester fiber from recycled plastic bottles and colored using an innovative water-free dyeing process, according to John Frazier, the company’s senior director of chemical innovation.

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BOTTLE TO BODY
Nike is using polyester fiber from recycled plastic bottles and supercritical CO2 water-free dyeing technology to make sportswear fabrics, as modeled by marathon world champion and Olympic medalist Abel Kirui.
Credit: Nike
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BOTTLE TO BODY
Nike is using polyester fiber from recycled plastic bottles and supercritical CO2 water-free dyeing technology to make sportswear fabrics, as modeled by marathon world champion and Olympic medalist Abel Kirui.
Credit: Nike

One forum that chemists and engineers have come to use as a springboard to showcase these types of developments is the annual Green Chemistry & Engineering Conference. Some 500 green-minded participants assembled June 17–19 for the 18th edition of the meeting, which was hosted by the American Chemical Society’s Green Chemistry Institute in the Washington, D.C., suburb of North Bethesda, Md.

“Green chemistry’s success has been the ability to translate sustainable innovations from the lab to the marketplace,” conference cochair James E. Hutchison, a nanomaterials expert at the University of Oregon, tells C&EN in explaining the conference’s theme, “Innovating for Sustainability.”

When green chemistry started 20 years ago, there was pull from industry in only a few areas, such as pharmaceuticals and agrochemicals, Hutchison says. Those industries could see the benefit of retooling syntheses and industrial processes to achieve more efficient and less hazardous ways of doing chemistry. Advances in toxicology and life-cycle analysis since then have prompted companies to take a greater interest in using green chemistry to design safer chemicals and products from the start. They have learned how these innovations can be used as a lever for working through regulatory issues and for connecting with consumers and satisfying shareholders.

“Now the pull is across a broad swath of industry,” Hutchison observes. “The academic community is also now more aware of what is necessary to support applied science, what is called use-inspired basic research. Green chemistry is perfect for that.”

The Nike example was explained further at the conference by Richard S. Blackburn, head of green chemistry at the Centre for Technical Textiles at the University of Leeds, in England. “Clothing is one of the few consumer products used by every person on the planet,” Blackburn said. “And growing demand from a growing middle class is why innovation in apparel and footwear is needed to meet sustainability challenges.”

Raw materials for fibers are one thing that needs to change, Blackburn noted. About 60% of clothing is made with synthetic fibers such as polyester and about 30% with natural cotton fiber, he explained. The sustainability challenge with synthetics is that they are nondegradable, consume nonrenewable petroleum feedstocks, and contribute to greenhouse gas emissions. And when it comes to cotton, natural doesn’t necessarily mean sustainable, Blackburn pointed out. Cotton requires a lot of water for irrigation and consumes about 25% of pesticides applied globally.

One option for sourcing synthetic fiber is by recycling polyethylene terephthalate from plastic bottles, he noted. As for cotton, solutions include developing more sustainable production and using other natural fibers. For example, Blackburn is working in collaboration with Austrian textile fiber producer Lenzing to study how to use eucalyptus wood pulp to make lyocell, a form of rayon produced from cellulose.

Beyond fiber, Blackburn described needs in improving fabric dyeing. Traditional dyeing also requires a lot of water—about 7 gal to dye a T-shirt—and is energy-intensive because the dyed material must be dried. Blackburn related how using supercritical carbon dioxide as the solvent in a water-free dyeing process could revolutionize the clothing and textile industry.

When under pressure and at slightly elevated temperature, CO2 functions like a liquid instead of a gas. It has long been used as a solvent for decaffeinating coffee and more recently in dry cleaning and some chemical manufacturing. But it wasn’t until Dutch start-up firm DyeCoo Textile Systems recently invented an industrial-scale process and equipment that supercritical CO-based dyeing became practical.

Blackburn went on to explain how Nike put recycled bottle plastic and supercritical CO2 dyeing together to create its ColorDry process, with the first products launched commercially on June 12. The process reduces dyeing time 40%, requires 60% less energy because drying isn’t needed, and reduces factory size 25% compared with traditional dyeing.

“Ultimately, the most sustainable thing we could do is design clothing with a longer lifetime so that we use fewer raw materials and buy fewer clothes,” Blackburn concluded. “That is not the trend right now, but it will be possible with better fiber and more durable dyeing. Key to ensuring a positive reception will be getting the clothing design community and retailers involved to help change the mind-set.”

In chemistry that involves a different kind of color, said electrical engineer Seth Coe-Sullivan, cofounder and chief technology officer of QD Vision. He spoke about the company being the first to commercialize quantum dots, by putting them in lightbulbs in 2010 and televisions in 2013. Coe-Sullivan described how his Boston-based company took quantum-dot research started at Massachusetts Institute of Technology and used the principles of green chemistry and life-cycle analysis to usher a promising yet environmentally problematic product into a competitive marketplace.

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‘GREEN’ LIGHT
QD Vision’s clean technology for producing quantum dots, contained in a slender tube is now being used in enhanced-color televisions (right).
Credit: QD Vision
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‘GREEN’ LIGHT
QD Vision’s clean technology for producing quantum dots, contained in a slender tube is now being used in enhanced-color televisions (right).
Credit: QD Vision

Quantum dots are semiconducting inorganic nanoparticles, such as cadmium selenide or indium phosphide, that emit light after being excited electronically. The color of light depends on the size of the particles, with larger particles emitting red, medium-sized particles emitting green, and the smallest particles emitting blue.

“This is a bit of quantum weirdness,” Coe-Sullivan related. “The different size alters the band gap of the semiconductor and thus the color emitted. It is one of the few examples of being able to actually see a quantum effect in action.”

Quantum dots have the highest color quality and are the most energy-efficient lighting technology known, Coe-Sullivan explained. But the technology is not known for being particularly “green.” The colloidal synthesis typically involves toxic metal alkyl precursors and unfriendly phosphorus-containing solvents such as trioctylphosphine oxide. Each batch is only marginally reproducible with modest yields.

In addition, nanoparticles have elicited environmental concerns because of the uncertainty of how the size of the materials might make them toxic—billions upon billions of quantum dots go into a single light-emitting diode (LED) lightbulb or TV display. Add in a heavy metal such as cadmium, which is already known to be toxic, and it only worsens the concern.

QD Vision makes quantum dots with a solid cadmium-selenide core coated with a cadmium-zinc sulfide shell and topped with organic ligands. The company turned to optimizing the synthesis by selecting less-toxic metal carboxylate precursors and more benign long-chain alkane solvents. Along the way the company’s researchers focused on reducing solvent use and energy consumption while improving yields and batch reproducibility.

The company’s display technology is based on filling a slender tube with quantum dots, Coe-Sullivan explained. The tube runs along the length of the display on one edge, and when the tube is lit using LEDs, the mix of precisely sized quantum dots provides a spectrum of color to light the display.

QD Vision proactively engaged regulatory authorities in the U.S. and Europe to navigate the approval process, Coe-Sullivan related. These agencies, working under the rules of the Toxic Substances Control Act in the U.S. and the Registration, Evaluation, Authorisation & Restriction of Chemicals management system in Europe, would like to keep cadmium out of consumer goods that are shipped around the globe and end up in people’s homes. Coe-Sullivan and his team effectively taught the authorities how the materials are made and the technology works, and in doing so made the case for allowing products containing cadmium quantum dots to go forward, despite regulatory restrictions.

“Risk and the perception of risk are hard to determine and manage,” Coe-Sullivan said. “If you can’t do that, why even make an innovative product?”

First off, the QD Vision team explained how the company’s cadmium-based quantum dots are less toxic than competing indium phosphide quantum dots, in part because of the greener synthesis and avoiding phosphorus-containing chemicals. Quantum dots also help reduce use of mercury and resource-constrained rare-earth metals in lighting and electronics.

But more important, the lightbulbs and TVs require a tiny amount of cadmium—only about 1 mg per TV display. In addition, QD Vision has shown that by reducing the amount of electricity consumed by a product such as a television, quantum dots actually help reduce air emissions of cadmium and greenhouse gases by burning less fossil fuel, in particular coal. The amount of cadmium entering the environment is less, even after making the quantum dots.

“That is a little mind-bending,” Oregon’s Hutchison says. “That is the kind of depth of analysis that needs to be happening more and more in chemistry. It has its foundation from two decades of green chemistry outreach and education.”

Eric J. Beckman, codirector of the Mascaro Center for Sustainable Innovation at the University of Pittsburgh, agreed. As a founder of a biomedical adhesives company, Beckman noted that green chemistry can enter anywhere in the process, including concept, design, materials selection, production, distribution, and use by the customer. As chemists and chemical engineers continue to integrate green chemistry and observe consumer needs, he added, they will be able to fill in additional gaps.

“Twenty years ago we had a hard time putting the words ‘green’ and ‘chemistry’ together,” Beckman said. “Green chemistry and its role in innovation and sustainability is now a positive benefit for chemists. It is helping chemistry become more important.” 

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Green Chemistry Gets A Boost From Open Innovation Platforms

Launch program and White House “maker” project provide opportunities for chemical innovation

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Credit: Launch
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Credit: Launch

In a bid to further enhance the impact of green chemistry, the open innovation research organization Launch has announced that its 2014 challenge will focus on green chemistry.

Launch was founded in 2009 by the National Aeronautics & Space Administration, sportswear company Nike, the U.S. Agency for International Development, and the Department of State to identify and foster breakthrough ideas for developing sustainable products and manufacturing technologies. The “making of things,” as it’s called, is being promoted for its positive global social, environmental, and economic impacts.

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A LITTLE STICK
The bioneedle’s degradable injection system offers a more efficient means of vaccination.
Credit: Launch
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A LITTLE STICK
The bioneedle’s degradable injection system offers a more efficient means of vaccination.
Credit: Launch

To harness new innovations, Launch has issued a series of global challenges with themes on textiles, fabrics, waste to energy, health, energy, and water. The challenges are contests of sorts in which the leading concepts for each challenge are selected and then supported by a team of science, business, and federal policy experts. The projects are promoted to gain visibility in the marketplace and move them forward toward commercialization. The founders have a vested interest in the innovations coming out of the Launch program to develop new products of their own that might assist space travel and aid people in developing countries.

Innovations such as these are just waiting to happen, said Nancy B. Jackson, who announced Launch’s green chemistry challenge on June 18 during the 18th Annual Green Chemistry & Engineering Conference. Jackson, a past American Chemical Society president and an expert in chemical weapons threat reduction at Sandia National Laboratories, is currently serving as a Franklin Fellow at the State Department.

“Limits wake people up,” Jackson said. “Sometimes when we are limited we find it depressing. But in this case having sustainability limits forces us to create something new—it’s a challenge to learn how to go beyond the limits.” Individuals can’t do this alone, she added, which is why partnerships such those facilitated by Launch are needed.

In explaining the program, Jackson provided an example: the bioneedle. For the health challenge, Launch has been seeking advances in developing simple, rugged, portable, low-power devices for remote medical diagnostic tests and treatment. One outcome was using a new degradable polymer to make tiny hollow needle-shaped vessels for administering vaccines. Vaccines are loaded into the bioneedles, which are painlessly injected into the skin with a puff of air and degrade within minutes. The vaccine no longer needs to be refrigerated, and there are no needles or syringes for disposal.

Jackson explained how she envisioned scientists and engineers using the principles of green chemistry and engineering during the challenge as a platform for other innovations like the bioneedle. The angles researchers might take include reducing the use of hazardous chemicals, developing low-environmental-impact renewable feedstocks, creating closed-loop manufacturing systems, and designing materials for end-of-life recycling. The green chemistry challenge is open for submissions through Sept. 24, she noted, with some of the entries possibly being drawn from presentations at the green chemistry conference.

“The open innovation approach goes a long way toward finding new competitive spaces,” added John Frazier, senior director of chemical innovation at Nike. “These sparks of innovation ultimately help bring to market technologies that may not otherwise ever see the light of day.”

As the green chemistry conference was taking place, President Barack Obama was at the White House hosting the first Maker Faire and proclaiming June 18 a National Day of Making.

Many people have gained access to technologies such as three-dimensional printers, laser cutters, easy-to-use design software, and other desktop machine tools, enabling them to design and build almost anything. The so-called maker movement that is now taking place represents an opportunity to more efficiently produce any kind of product on demand, from printing a book to preparing packaged food to building a car.

“Most chemists are unaware of this movement, but chemistry is at the heart of the maker project,” Paul T. Anastas of Yale University told C&EN. One of the founding fathers of green chemistry and a former head of EPA’s Office of Research & Development, Anastas was invited to participate in the Maker Faire.

Anastas was enthusiastic about how the new movement is an opportunity for chemists and chemical engineers to innovate. He envisions that universities and local communities will increase efforts to provide space and equipment for people with innovative ideas to develop them into new products and processes. “I think this is going to change the way we think about doing chemistry,” Anastas said.

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Green Business Plan Competition Fosters Innovation

Conference event encourages research, development, and marketing of industrially relevant green products and processes

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WASTE TO PLASTIC
U.S. Bioplastics’ Gatoresin polyester is made from ferulic acid derived from biomass waste.
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WASTE TO PLASTIC
U.S. Bioplastics’ Gatoresin polyester is made from ferulic acid derived from biomass waste.
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SioTeX’s Kotwal (from left) poses with colleague Lisa Taylor, business plan competition judge Dan Daly of the Alabama Innovation & Mentoring of Entrepreneurs Center, and SioTeX team mentor chemistry professor Gary Beall of Texas State University, San Marcos.
Credit: Peter Cutts Photography
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SioTeX’s Kotwal (from left) poses with colleague Lisa Taylor, business plan competition judge Dan Daly of the Alabama Innovation & Mentoring of Entrepreneurs Center, and SioTeX team mentor chemistry professor Gary Beall of Texas State University, San Marcos.
Credit: Peter Cutts Photography

A start-up firm developing a drop-in replacement for the popular paint, tire, and plastic additive fumed silica took top honors at this year’s Green Chemistry Business Plan Competition. The competition, held as part of the annual Green Chemistry & Engineering Conference, provides the chance for sustainability-oriented entrepreneurs to get some help in moving their innovations closer to commercial reality.

For the competition, business plans submitted by 12 companies were judged in a preliminary round. A social media campaign allowed people to go online and view one-minute elevator pitch videos by the finalists and make a financial contribution to buy votes for their favorite team. The online campaign raised $3,100 toward the $10,000 cash prize for the winner.

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Credit: SioTeX
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Credit: SioTeX

“Our goal was to bring a broader awareness to green chemistry and involve people beyond the competitors,” said Savannah Sullivan, a research associate at the American Chemical Society’s Green Chemistry Institute, which sponsored the event. “Everyone has a stake in this game of greener chemistry and entrepreneurship.”

Four finalists attended the conference to make formal presentations. A three-member panel judged the finalists on the basis of how well their products meet green chemistry standards, which include providing an equivalent function to an existing product, the potential to perform as well as or better than a product it would replace, being available at a competitive or lower price, and having a minimum environmental impact for all processes involved in its production and use. The judges also relied on the online buy-in to make their decision.

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SioTeX burns pretreated rice hulls in a tube furnace to make its Eco-Sil fumed silica.
Credit: SioTeX
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SioTeX burns pretreated rice hulls in a tube furnace to make its Eco-Sil fumed silica.
Credit: SioTeX

SioTeX, with headquarters in San Marcos, Texas, won for Eco-Sil, a green replacement for fumed silica, an important but energy-intensive materials additive. Eco-Sil is made by roasting waste rice hulls, a renewable silica-containing raw material that avoids toxic silicon tetrachloride normally used to make fumed silica. “This has been a great opportunity to help us better our business,” said Ash Kotwal, SioTeX’s vice president of manufacturing.

The runner-up, U.S. Bioplastics, based in Orlando, is developing Gatoresin, a biobased polymer made from ferulic acid that is derived from the paper production by-product lignin and other plant waste such as sugarcane bagasse. The degradable polyester is initially being marketed for short-term-use plastic products such as packaging.

The other finalists included Cell-Free Bioinnovations, of Blacksburg, Va., which is developing disposable sugar-powered enzymatic fuel cells as high-energy-density batteries, and Australia-based Circa Group, which is advancing a continuous process for turning waste cellulose into levoglucosenone, a cyclic C6 molecule that could be used as a feedstock to make biobased solvents, flavor compounds, and polymers.

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Natural Biocide Offers An Alternative For Fracking

Bacteria-derived lipopeptide could help manage bacterial fouling of oil and gas wells

A bacterial lipopeptide with surfactant properties has been identified as a low-toxicity biocide for controlling nuisance bacteria that often foul oil and gas wells. Darren Maley of Trican Well Service, a Canadian oil- and gas-field services company, described the biocide and its performance in lab and field tests during the 18th Annual Green Chemistry & Engineering Conference.

During hydraulic fracturing and other well extraction processes, an assortment of chemical additives are used in small amounts to optimize oil and gas recovery, Maley explained. Biocides prevent growth of bacteria that can form films and clog wells. The bacteria also produce compounds that are corrosive to well equipment and can sour the oil or gas.

Commonly used biocides include glutaraldehyde, 2,2-dibromo-3-nitrilopropionamide, and quaternary ammonium compounds, he said. These biocides are very effective, Maley added. However, among the chemical additives in well-drilling biocides, they are generally the most toxic to people and the most environmentally problematic. With worker safety, the environment, and societal concerns in mind, oil and gas companies are seeking alternatives, he noted.

The cyclic lipopeptide surfactin produced by Bacillus subtilis has been known for some time for its antibiotic properties and is already used, for example, in the bioremediation of oil spills. The molecule’s amphiphilic properties enable it to interact with and shred bacterial cell walls. Maley and his colleagues decided to try a low-cost extract containing surfactin and found that it has good efficacy versus common oil-field bacteria over a range of pH and temperature conditions. It also provides a better environmental profile than currently used biocides. Trican is now awaiting regulatory approval to start using surfactin in its Canadian and U.S. operations.

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Sigma-Aldrich Develops Green Cross-Coupling Reaction Kits

Off-the-shelf kits allow single organic synthesis reactions to be performed in water for research and in teaching labs

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E IMPROVEMENT
Running this Suzuki-Miyaura coupling reaction in a micellar solution using TPGS-750-M, a designer surfactant, improves the yield and significantly reduces the environmental profile, or E factor, of the reaction.
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E IMPROVEMENT
Running this Suzuki-Miyaura coupling reaction in a micellar solution using TPGS-750-M, a designer surfactant, improves the yield and significantly reduces the environmental profile, or E factor, of the reaction.

Sigma-Aldrich has added single-use cross-coupling reaction kits to its iconic chemical supply catalog. These new kits for Suzuki-Miyaura, Buchwald-Hartwig, Sonogashira, and Heck reactions contain a catalyst, ligand, base, and surfactant solution preweighed into disposable ampules in the appropriate stoichiometry for a 1-mmol reaction.

The kits are based on chemistry developed by Bruce H. Lipshutz of the University of California, Santa Barbara. Lipshutz and his team designed a surfactant (TPGS-750-M) specifically to use with transition-metal catalysts so that common organic reactions can be run in water and avoid organic solvents. The surfactant creates optimally sized micelles that serve as nanoreactors. Lipshutz received a 2011 Presidential Green Chemistry Challenge Award for the technology.

The new kits, part of Sigma-Aldrich’s Greener Alternatives product initiative, are designed to be an off-the-shelf, complete experiment suitable for testing a reaction, noted Subir Ghorai, a former postdoc in Lipshutz’s group who now works in product development for Sigma-Aldrich. Lipshutz and Ghorai discussed the kits with C&EN during the 18th Annual Green Chemistry & Engineering Conference.

The kits relieve the burden of buying larger amounts of individual reagents that may later go unused or relying on reagents that have been sitting on a shelf and are no longer fresh, Ghorai said. Coupling partners must be provided by the user, but a recommended reaction procedure is included with the kit to help ensure the user will stand the best possible chance of running a successful reaction. In contrast to other kits sold by Sigma-Aldrich and other chemical suppliers, the new kits are the first meant to be consumed all at once and are not intended for screening and optimizing reactions.

“They are complementary to our catalysis and reagents product lines, and we believe the kits offer a solution for those who are seeking more sustainable ways to do common chemistry,” Ghorai said. “We envision that these could be useful to chemists who are interested in testing the feasibility of their reactions before purchasing the reaction components in larger quantities. We think they also can be used as a lab-in-a-box for teaching labs.”

The first version of the kits is selling for $100. But Lipshutz and the Sigma-Aldrich team are working on a second edition that is even easier to use, more aesthetically pleasing, and expected to cost only $40. They are also working on expanding the kits to include other types of reactions.

“I really believe in this chemistry,” Lipshutz said. “I want to get it out to the community so other chemists can see what is possible.”

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EMD Millipore Makes Progress In Biopharma Plastics Recycling

Company develops take-back program to reduce amount of plastics used in biopharmaceutical production that ends up in landfills

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Biopharma lab filters collected for recycling.
Credit: EMD Millipore
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Biopharma lab filters collected for recycling.
Credit: EMD Millipore

As the biopharmaceutical industry turns increasingly to single-use manufacturing products, companies have been thinking about how they can be environmentally responsible when it comes to disposing of manufacturing waste, which includes a mix of materials that sometimes contains biohazards. To accommodate that need, EMD Millipore has been partnering with its customers to develop a recycling program to test the feasibility of collecting and recycling filters, tubing, bag assemblies, and packaging.

EMD Millipore is known for its water filtration products and other consumable products used in biological research and manufacturing. “I love plastic,” EMD Millipore’s Jacqueline Ignacio said. “It is a wonderful material to work with. But it is a challenge in this industry to decide what to do with it at the end of a product’s life cycle.” At the 18th Annual Green Chemistry & Engineering Conference, Ignacio announced initial results from the company’s recycling effort.

“Researchers tend to think linearly about the supply chain in this industry,” Ignacio said. “But it really should be thought of as a closed loop, and that is the direction we are heading.”

After researching the problem and instructing customers about which materials can be recycled, the company developed a collection system and contracted with a recycling firm to process the materials. So far, some 112 tons of materials have been diverted from landfills from a handful of customers who have been trying the program. About half of the material has been recycled into new plastic products, with the remaining half being burned as an alternative fuel source to generate heat at a cement kiln.

EMD Millipore believes it has a responsibility to work with its customers to tackle the recycling challenge and to ensure that its operations and products are more sustainable over the long term, Ignacio said. On the flip side, feedback from customers about recycling is helping to inspire new product development and redesign toward products that are more sustainable and easily disassembled for recycling, she added. For now, the program costs money, Ignacio admitted, but the company is expecting the recycling to become cost-neutral as it continues and expands globally.

 
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