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Universities can be a major resource for industrial innovation, especially when the two collaborate to generate new knowledge and impact. Engaging with academia is key to the strategy of the ACS Green Chemistry Institute’s Pharmaceutical Roundtable. Year after year, the Roundtable delivers on this priority by providing grants for academic-industrial research collaborations ($1.5 million since 2005) and hosting events that act as a bridge between university research and company application. To kick off their 10-year anniversary celebrations, the Roundtable hosted an all-day catalysis symposium in conjunction with their Spring Meeting in Basel, Switzerland.

 

Roland Thieme, the Head of Chemical Development and Supply at F. Hoffmann-La Roche (the co-host of the symposium), and Juan Colberg, Senior Director at Pfizer and co-chair of the Roundtable, opened the symposium. Their introduction illustrated how the title of the event, “Green Chemistry Makes a Difference: Innovations leading to a more sustainable pharmaceutical industry,” summarizes the mission of the Roundtable—to catalyze the implementation of green chemistry and engineering in the global pharmaceutical industry. For 10 years, the Roundtable has executed on this mission based on their strategic priorities (to inform and influence the research agenda, provide tools for innovation, act as an education resource, and collaborate globally) and, since 2007, a set of key research areas. These research areas are topics that all companies were consistently encountering and seeking greener alternatives for. They were determined via a brainstorming and voting process by the Roundtable, which resulted in three categories the group would target for the next eight years in their initiatives: reactions currently used but better reagents preferred, more aspirational reactions, and solvent themes.

 

A theme that persists throughout most of these key research areas is catalysis, a fundamental pillar of green chemistry. The Roundtable seeks to not only further employ catalyst technologies in pharmaceutical science, but ensure that the approaches are greener than what currently exist (such as moving away from use of precious metal catalysts). With the goal of triggering innovation in approaches to and applications of catalysis technologies, the symposium in Basel featured six professors based in Europe who are leaders in the field and hosted nearly 20 posters from students, academics, and industry professionals.

 

Basel Symposium.jpgSymposium speakers from left to right: Marc Taillefer, Uwe Bronscheuer, Katalin Barta, Benjamin List, Janine Cossy, and Michael North.

 

“The Roundtable convenes events like this symposium to foster discussion between academic and private sector around potential greener commercial approaches, by influencing the new technology research agendas. We are very excited to host these distinguished speakers, as each address important and innovative approaches to make organo, enzymatic, and transition metal catalysis in pharmaceutical science more sustainable. These professors are discussing some of the biggest problems facing the industry with respect to catalysis such as limited supply, toxicity, cost, and solvent volume. One example is the strides made around minimizing the use of precious metals by looking to more sustainable options like iron, nickel and copper--metals that are obtained via cleaner mining processes and provide lower supply risk from more stable mining conditions. Additionally, catalytic methods to access renewable raw materials from biomass were highlighted, establishing sustainable alternatives to petroleum products needed to make life-saving medicines” said the Roundtable co-chairs.

 

The first talk was from Professor Benjamin List of the Max Planck Institute—Mülheim (Germany), who discussed an approach to enantioselective synthesis called “asymmetric counteranion directed catalysis.” This technique can be applied to several reactions (such as alylation, phosphylation, etc.), many of which are frequently employed by the pharmaceutical industry. List was followed by Professor Katalin Barta of University of Gronigen (Netherlands). She focused on strategies for the conversion of biorenewables through sustainable catalysis with earth abundant metals. The approaches Barta presented not only provide catalytic innovations for the industry, but will lead to renewable-based (rather than petroleum) starting materials the industry depends on everyday as reagents and solvents. Professor Marc Taillefer of ENSC Montpellier (France) wrapped up the first half of talks with his work, which utilizes copper and iron catalysts that allow for a wide range of transformations (achieving C-C, C-O, and C-N bonds) under significantly milder conditions than traditional approaches.

 

Between the talks and during meals throughout the day, attendees were able to peruse the poster session highlighting work ranging from one-pot cascade reactions to ball-milling as a solventless reaction. “I genuinely believe that society cannot continue at current consumption levels, and as chemists we can address this by moving towards new, sustainable approaches, such as batch to flow processes. This symposium has brought together a lot of people from many companies, yet is small enough so that everyone can talk to everyone and discuss real-world problems and solutions,“ said G. Kemeling, the Editor in Chief of ChemSusChem.

 

After lunch, the symposium attendees flowed back into the auditorium to hear Professor Uwe Bornscheur of University of Greifswald (Germany) discuss enzyme discovery, engineering, and application in biocatalysis. Bornscheur walked the audience through the history of how enzymatic processes have been able to replace chemical routes, and used his work to show a broad range of enzyme-catalyzed reactions that are efficient, highly selective, and can be achieved under mild conditions with less by-products than equivalent chemical routes. Professor Janine Cossy of ESPCI Paris (France) followed with a talk filled with approaches to cyclization and coupling that replace palladium catalysts with a variety of alternative and greener catalysts (such as the more abundant iron). The molecules she focuses on (macrocyclic) are currently under-exploited by industry (accounting for only 2% of orally available molecules on the market, currently useful for anti-tumoral activity), but her work can deliver steps to these molecules with more benign chemistry. The symposium closed with Professor Micheal North from University of York and the Green Chemistry Centre for Excellence (England). His talk highlighted his group's bimetallic catalytic approach that allows for transformation of carbon dioxide to cyclic carbonates, as well as applications of these carbonates as green solvents. By making use of waste CO2 and moving towards flow chemistry, the research is delivering ethylene carbonate and propylene carbonate as possible solvent replacements for DMF, DMSO, and other toxic media sometimes present in pharmaceutical science. Another emphasis of North's talk was the importance of outreach, to both student groups and industry, which the Centre incorporates into each of their project areas.

 

John Tucker, a senior scientist at Amgen and co-chair of the Roundtable, closed the day's events with a summary of how these talks had already instigated much inspiration and conversation for future innovation. Whether it was the elegant cascade reactions facilitated by enzymes or the replacement of unsustainable metal catalysts, the symposium offered a wide array of technologies that have the potential to transform the industry. As the Roundtable looks to their next ten years they aspire to continue delivering on their strategic priorities, and bridge academic and industrial communities throughout the world to make their science more sustainable. The 10-year anniversary celebrations will continue throughout the year, with the next events taking place at the 19th Annual Green Chemistry and Engineering Conference in the Washington, DC area (USA) and the 250th ACS National Meeting and Exposition in Boston, MA (USA). The Roundtable will also be releasing an update of their key research areas, discussing new focus areas, as well as actions and progress to date. For more information, please visit the Pharmaceutical Roundtable’s website and for Roundtable updates and announcements, follow ACS GCI on social media (Twitter, Facebook, and LinkedIn).

 

“The Nexus Blog” is a sister publication of “The Nexus” newsletter. To sign up for the newsletter, please email gci@acs.org, or if you have an ACS ID, login to your email preferences and select “The Nexus” to subscribe.

 

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Contributed by David Constable, Director, ACS Green Chemistry Institute®

 

There is always a lot going on in green chemistry and engineering, which is a great thing. I sometimes hear that many people don’t think that is the case and believe that more should be done and at a faster pace. But, from where I sit, there is a lot going on and green chemistry is being discussed and implemented more and more with each passing day.

 

Just take the ACS National Meeting as one example. For anyone who hasn’t been to an ACS national meeting, you should try and go at least once to experience the breadth and depth of the meeting. On any given day, several technical divisions are sponsoring sessions on some aspect of chemistry that falls under the umbrella of sustainable or green chemistry and engineering principles. These sessions aren’t always labeled as sustainable or green chemistry or engineering, but a quick look at what is being presented should demonstrate that there’s a lot to offer in these areas. To be clear, what is being presented isn’t always about toxics elimination either (actually, it usually isn’t) and the presenters may not actually consider what they are doing to be sustainable or green chemistry and engineering, but that doesn’t mean it isn’t. The bottom line for me is that I’m greatly encouraged to see all the programing that is available at the ACS National meetings and I hope that it continues.

 

Another major event for the ACS GCI that is not terribly apparent to anyone outside of the Institute, is our twice a year Board meeting. For those who are unfamiliar with the ACS and how it operates, there are many governance structures to oversee the work of the ACS, and one of those is the ACS GCI Board. For a complete list of who is on the ACS GCI Board click here. The Board is responsible for overseeing the work of the ACS GCI, sets its strategic direction, and discusses what it thinks we should be doing. We had a good meeting in early April and some excellent discussions on several projects, partnerships and alliances with other green chemistry organizations, and how best to proceed in a world of ever-increasing green chemistry and engineering organizations.

 

The same week of the Board meeting the Organizing Committee for the Green Chemistry and Engineering Conference met to finalize the technical program for the 2015 conference scheduled for July. The Conference is shaping up to be another great year with solid technical programming thanks to the hard work of the organizing committee and their session chairs. Many don’t realize that the Organizing committee has been at work since last summer and very engaged in making the conference a reality. For those of you that had not heard elsewhere, we were greatly saddened by Dr. Richard Wool’s untimely passing in late March. Richard had been such a strong force in green chemistry and engineering for a long time and was very active and committed to making the conference a great event this year. We will miss him greatly, but we were pleased to welcome to the organizing committee a former student of Richard’s, Dr. Joseph F. Stanzione, a professor at Rowan University, to take up where Richard left off. Finally,

 

I’d like to acknowledge the ACS GCI Pharmaceutical Roundtable's successful meeting in Basel, Switzerland, the week of 13 April. For those of you that don’t know, the Pharma RT is celebrating its tenth year anniversary  and in addition to their normal meeting, they had a great one-day symposium on green chemistry to help them celebrate. The ACS GCI Pharma RT continues to make a number of significant contributions to green chemistry and engineering, and I look forward to their continuing success over the next ten years.

 

So, I’ll end as I began; there’s a lot going on in green chemistry and engineering, and while it may not be apparent to everyone, it’s undoubtedly a good thing. As always, please do let me know what you think.

 

 

 

“The Nexus Blog” is a sister publication of “The Nexus” newsletter. To sign up for the newsletter, please email gci@acs.org, or if you have an ACS ID, login to your email preferences and select “The Nexus” to subscribe.

 

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Although there is no official government ranking of which city is the most sustainable city in the United States, a constant contender on the numerous amateur lists has been Portland, Oregon.

 

According to the International Business Times, some of the factors involved in being considered a sustainable city are the size of the city’s “carbon footprint”, number of certified buildings designed with minimal nonrenewable energy use, reduced water consumption, and cities with high proportions of green space. Travel and Leisure dubbed Portland the number one greenest city in America in 2015, “for its mass transit and near the top for its groovy, offbeat locals, known for their DIY spirit and cycling culture.”

 

877440523_83256c2402.jpgThe Portland Bureau of Planning and Sustainability (BPS) , “develops creative and practical solutions to enhance Portland’s livability, preserve distinctive places and plan for a resilient future”. They list the numerous ways the city strives to be more sustainable, such as having green buildings—a way of designing and constructing buildings to increase performance and enhance the health and experience for people who work, live and play in these structures. The city saves water and energy, generates low carbon emissions, uses renewable energy and more.

 

Jennifer Allen, associate professor of public administration and director of the Institute for Sustainable Solutions (ISS) at Portland State University, stated “They [BPS] lead the development and implementation of our Climate Action Plan – Portland was the first city in the U.S. to have such a plan, and BPS does a great job of engaging all the relevant partners in exploring how we can meet the goals of the plan.”

 

Allen has worked in the field of sustainable development since 1987, and first began working at the World Bank on efforts to better integrate environmental and social considerations into international development. Her stance on sustainable cities starts with the understanding of how people make choices every day, and ways to encourage valuing and conserving their resources.  “We need engineers, urban planners and other design thinkers to bring innovative strategies to the table to enable us to get around with a smaller environmental footprint, and to reframe topics such as infrastructure development to better integrate natural systems. Taking a more integrated approach to planning and development is a critical step. For example, Portland seeks to promote ‘20 minute neighborhoods’ that allow residents to access the basic services they need without traveling long distances,” Allen stated.

 

Now, you’re probably thinking, “why are you highlighting the city of Portland when there are multiple cities making every effort to be more sustainable?” Well, dear reader, since this month’s issue of The Nexus e-newsletter is themed Sustainable Cities, we wanted to take this moment to announce that the 20th Annual Green Chemistry & Engineering Conference (GC&E), to be held in 2016, will be hosted in Portland, Oregon.

 

Jennifer MacKellar, the ACS Green Chemistry Institute® Program Manager, stated that hosting GC&E 2016 in Portland is “an exciting opportunity to engage new audiences, revitalize the content and leverage our west coast partners. There is a lot happening in the green chemistry/sustainability space in the Portland and the west coast area that we can highlight through our technical sessions.”

 

The conference will be held at the Portland Hilton & Executive Tower, which has several green practices, including a robust recycling program, food composting, energy efficiency, water conservation, waste minimization and using greener products. They also try to locally source their food as much as possible, “these were important factors for us when choosing a meeting location”, stated MacKellar. There are several companies that support green chemistry in the Portland area. Nike in particular, has been a huge supporter of green chemistry and has worked very hard to include green chemistry into their corporate practices. There are also several universities in the region that have strong green chemistry programs, including University of Oregon, Oregon State, UC Berkeley, and Portland State University. Offering our 2016 conference in the Portland area will give enthusiastic green chemistry students a great opportunity to attend without the high travel costs.

 

Portland is just one of many sustainable cities, not only in the country, but the world! ACS GCI is excited to continue the planning for the 20th GC&E Conference and we hope to see you in Portland in 2016!

 

 

 

“The Nexus Blog” is a sister publication of “The Nexus” newsletter. To sign up for the newsletter, please email gci@acs.org, or if you have an ACS ID, login to your email preferences and select “The Nexus” to subscribe.

 

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Contributed by Douglas Fox, Department of Chemistry, American University, Washington, DC

 

Our research group helps to improve the sustainability of buildings and cities by focusing on the development of affordable and effective flame retardants that are synthesized from natural products. These flame retardants are blended with plastics or formulated into a coating for use in flexible foams and wood based products. Some have been used in bio-derived plastics to reduce their flammability without the typical degradation of desirable polymer properties, thereby increasing the number of commercial applications for these types of plastics.

 

Plastics, polymers, and polymer composites have become ubiquitous over the past 60 years. In 2013, nearly 300 million metric tons of plastic were produced, making it one of the most used materials worldwide on a volume basis. Their increased use can be traced to their inherent properties: strong, lightweight, flexible, moldable, and inexpensive.  In addition, it is relatively easy to incorporate additives to tune their properties. These composites can be tailored to achieve desired properties on opposite ends of the spectrum by simply mixing molten polymer and filler using an extruder.

 

For example, addition of glass, carbon, or natural fibers increase strength and stiffness. Addition of a plasticizer decreases tensile strength and softens the composite. Addition of clay can reduce diffusion of gases or solvents, whereas incorporation of water soluble salts during extrusion can increase voids in the processed plastic. Or, the addition of benzophenones aids used to protect the polymer from photodegradation, while the addition of titanium dioxide can be used as a photoinitiator to accelerate UV degradation of the polymer.  But plastics also come with a range of disadvantages, presenting major challenges. They are inherently flammable, increasing the risk and costs of fire.  Most of the monomers, or building blocks of the polymer, and many of the fillers used to tailor the properties, are toxic, bioaccumulative, or persistent chemicals, posing many health concerns, both real and perceived. And, they are generally durable. Combined with their low densities (lightweight), this generates a major waste management issue. Recycling has alleviated some of the waste burden, but plastics still represent over 20% of the waste in landfills, and over 5 million tons of plastic finds its way in oceans every year.

 

Nexus picture.jpgOne of the more difficult disadvantages to address is the high flammability of plastics. In the United States, fires account for over 3,000 deaths, 16,000 injuries, and $11 billion in property loss every year. This represents a major decline over the past few decades. Part of this reduction can be attributed to the use of flame retardants in residential upholstered furniture, which reduce the toxicity of combustion products and allow for longer egress times during fires. Fires can be started by either open flame sources, such as candles or matches, or by smoldering sources, such as cigarettes or incense. There are many methods that can be used to address these problems, such as use of smolder resistant fabrics, back-coating fabrics, or the addition of flame retardants. Recently, there has been increasing concern over the migration, persistence, potential toxicity, and perceived lack of efficacy of flame retardants typically used in furniture and flexible foam. This has led to public debate, regulation changes, and increased pressure to find alternatives. The alternatives include both approaches to reducing fire risks as well as development of safer, less transient, more efficient flame retardants.

 

The largest concern of the increased use of plastics is probably the problems associated with their disposal. There is an increased public awareness of the growing risks associated with waste, pollution and the need for more sustainable products and practices.  The most widely used plastics are synthesized from petroleum distillates, generating a resource and energy sustainability issue.  These plastics do not biodegrade, but will photodegrade into smaller fragments. This leads to the leaching of the starting materials and fillers used in the production of the composites, many of which are toxic to plants and animals alike. In addition, the small photodegraded plastic fragments are consumed by animals in the wild, which are also toxic or disruptive to their life cycle. This persistence, bio-accumulation, and toxicity of leached chemicals leads to a loss in biodiversity, which can affect the sustainability of entire ecosystems. Resolving this issue is quite complex due to technical, societal, economic, and logistical issues. Attempts have been made to produce biodegradable plastics and/or plastics from bio-derived sources, such as starch based plastics, soybean based epoxies, and corn based poly(lactic acid). Unfortunately, these plastics possess properties that are inferior to their petroleum based counterparts and often cost much more to produce. There are a large number of scientists and engineers working on addressing these issues, and much progress has been made. With the addition of select additives and cheaper production practices, these bio-based and biodegradable plastics have slowly been making their way into the marketplace. Much of their use today has been limited to plastic utensils and packaging applications, but their blends with more traditional petroleum based plastics have also been explored for use in textiles and electrical equipment.

 

We are addressing these issues by developing more sustainable polymer nanocomposites with improved flame resistance and better compatibility between the filler and polymer. These composites would be used primarily in the home or businesses, helping to develop more sustainable cities. We have two primary goals in our work:

 

  1. The use of fillers and crosslinkers to improve the water resistance and mechanical properties of bio-derived polymers.
  2. The modification of natural materials to improve both interfacial adhesion and flame retardant properties of the polymer.

 

In many of our systems, we have addressed issues in both of these areas simultaneously.

 

Our primary focus is currently on the development of flame retardants using natural materials. We began with using cellulose as a replacement for one of the components in an intumescing flame retardant. An intumescing flame retardant produces a foaming char barrier through the use of a dehydration source (typically an acid), a carbon source (such as pentaerythritol), and a gas forming source (typically a polyamine). The use of cellulose fibers is more sustainable than traditional carbon sources used in intumescing flame retardants and can improve mechanical strength and stiffness if there is good interfacial adhesion with the polymer. To increase the amount and mechanical durability of the char during combustion, we utilized silicon containing materials. The modification of cellulose using a reactive POSS molecule (POSS is a hybrid between silica (SiO2) and silicone (R2SiO) that can be attached directly to polymer chains) was effective for flame retarding poly(lactic acid) while preventing the hydrolytic decomposition of the polymer during processing and preventing the loss in mechanical properties that typically accompanies this hydrolytic decomposition. The addition of organically modified clay was only partially effective due to the inability to fully separate the clay layers during processing.

 

Intumescing flame retardants suffer from the need for multiple components with variable surface energies and morphologies as well as moisture sensitivity, leading to the leaching of flame retardant during weathering and poor interfacial adhesion with some polymers. We are examining methods to utilize cellulose fibers for an all-fiber intumescent.  We phosphorylated the POSS modified cellulose to add the acid source needed to promote char. The level of phosphorylation was insufficient to replace typical acids, but the improvements observed were encouraging for future studies.  We recognized that starting with cellulose nanocrystals (CNCs), which have greater reinforcing potential, may be more advantageous than using cellulose fibers. CNCs that are produced from oxyanionic acids (like sulfuric acid) participate in side esterification reactions with the oxyanion. Use of sulfuric or phosphoric acid would produce CNCs that contain acidic sulfur or phosphorus groups, both of which are typically good flame retardants.  We have experimentally determined that sulfuric acid produced CNCs have a lower thermal stability but better flammability characteristics than unmodified cellulose fibrils. We are currently developing modification methods to simultaneously increase the thermal stability of the CNCs and modify the surface energy to improve interfacial adhesion with hydrophobic polymers.

 

It is difficult to homogenously disperse cellulose fibers or crystals in epoxy thermosets. Most epoxies are quite hydrophobic (poor interfacial adhesion), have high viscosities (mixing difficulties), and take hours to cure (time for suspensions to settle). For these systems, we examined the use of lignosulfonate and tartaric acid as an intumescing flame retardant. Lignosulfonate, which is a by-product of the sulfite pulping process, was very effective as a flame retardant for epoxy composites, but it had a tendency to migrate to the surface during curing.  As a result, the protective layer that forms can crack and peel off the surface when exposed to a radiant heat sources for too long.  We are currently investigating methods to prevent this migration during epoxy curing.

 

The largest fuel source in a home is upholstered furniture. To reduce the fire risks associated with them, the foam had been required to pass both smoldering and open flame fire tests. Manufacturers typically used brominated flame retardants to pass the open flame tests. Due to increasing concern over the persistence, potential toxicity, and perceived ineffectiveness of these flame retardants, industry has renewed interest in flame retardant alternatives. The newest regulations for upholstered furniture does not require an open-flame test, but that does not eliminate the risks associated with these type of fires nor guarantee that they will not be re-established. As a result, there is still an urgent need to develop more environmentally benign flame retardants for upholstered furniture or flexible foam.  In light of these developments, we have been developing flame retardant coatings using natural materials.  We use borate salts (which have been used extensively in wood as anti-fungal agents), phytic acid (which is a phosphate storage molecule in plants), or taurine as the primary flame retardant. To keep the flame retardant from washing away, we use carbohydrates, polydopamine, or food proteins as binding agents. Other natural additives to add char strength, anti-fungal properties, smoldering resistance, or binder crosslinking are currently under investigation.

 

As we design our approaches, we remind ourselves of the need to maintain processability. This includes both process design as well as operating costs.  It is my belief that great studies in sustainable materials and chemistry will not actually improve sustainability unless industry and commercial enterprises are able to technically and economically adopt the process. We welcome additional input from engineers, managers, and industry, especially on optimizing processing techniques, to help us achieve useful, ecologically sustainable products commonly found in homes and cities.

 

 

 

“The Nexus Blog” is a sister publication of “The Nexus” newsletter. To sign up for the newsletter, please email gci@acs.org, or if you have an ACS ID, login to your email preferences and select “The Nexus” to subscribe.

 

To read other posts, go to Green Chemistry: The Nexus Blog home.

Henry Ford:

 

“For a long time now, I have believed that industry & agriculture are natural partners & that they should begin to recognize & practice their partnership. Each of them is suffering from ailments which the other can cure. Agriculture needs a wider & steadier market; industrial workers need more steadier jobs. Can each be made to supply what the other needs? I think so. The link between is Chemistry. In the vicinity of Dearborn we are farming twenty thousand acres for everything from sunflowers to soy beans. We pass the crops through our laboratory to learn how they may be used in the manufacture of motor cars &, thus provide an industrial market for the farmers' products."

 

Source: Ford News, p.49, March 1933

When you go out to buy a shiny new Ford, you may be thinking about fuel efficiency, but you probably are not thinking about what the foam in your seat is made out of.

 

0ef9196.jpgLuckily, Dr. Deborah Mielewski is. She is the senior technical leader of the plastics research group at Ford Motor Company Research. Carrying on in the same vein as the company’s founder (see side panel), Mielewski has successfully researched, developed and  implemented a number of innovative materials made from a wide variety of agricultural and recycled products.

 

From soybeans in your seat to wheat straw in your storage bins to coconut fiber in your trunk liner to rice husks in your car’s electrical assembly—there is no shortage of ideas her team is working on.

 

Mielewski has Ph.D. in Chemical Engineering from the University of Michigan in Ann Arbor and has been working at Ford for 28 years.

 

She first brought her ideas to the executives at Ford in 2001 (and got immediate support from Bill Ford, then CEO and Henry Ford’s great- grandson), but it took until the price of oil started to rise to gain traction broadly both within and outside the company. Today, Ford has a sustainability vision that states that “recycled or renewable materials will be selected whenever technically and economically feasible.” Ford also makes it clear that renewable resources should not compete with the food supply—addressing a common concern surrounding the growth of biobased feedstocks.  Many of the materials are waste or byproducts of the food industry like rice and oat hulls.

 

So far, many bio-based products have passed the test of being technically and economically equivalent (or better) for a number of different applications on vehicles. The average vehicle contains 17-19% by weight plastics, textiles and natural materials.  The use of plastics has been driven by the desire to decrease the overall weight of the vehicle in order to increase fuel economy. It is in this area Mielewski and her team have been hard at work innovating.

 

The average Ford vehicle today uses 20-40 pounds of renewable materials. Examples include:

 

  • SoyFoam-sm.jpgStarting with the Mustang in 2007 and now present in all of Ford’s vehicles built in North America, Ford uses soy-based foam in seat cushions, backs and in 75% of head rests (pictured right). This adds up to 31,215 soybeans for every vehicle, or over 5 million pounds per year. The soy foam replaces petroleum-based foam, reducing saving approximately 20 million pounds of CO2 annually and reducing ozone depleting Volatile Organic Compounds (VOCs) by 67%.
  • Since 2010, Ford’s Flex cars have been produced with wheat straw reinforced storage bins—creating a market for another agricultural waste product and reducing CO2 emissions by 30,000 lbs annually (pictured bottom left).
  • Beginning in 2012, the Ford Focus electric car contains trunk mats made from coconut fibers—yet another agricultural waste product.
  • Since 2014, Ford’s popular F150 trucks contain rice husk reinforced plastic in their electrical harness. Rice husks, or the shells, are a waste product, so using them creates a market for  45,000 lbs of the material per year, all sourced from farms in Arkansas.
  • Also in 2014, tree-based cellulose (a byproduct of the lumber industry) replaced fiberglass in structural armrests in the Lincoln MKX (pictured bottom right).
  • In partnership with Coca-Cola, Ford has demonstrated the use their PlantBottleTM technology—a PET plastic made from renewable sources—to create automotive fabrics, carpet and headliners for the Ford Fusion Energi.
  • Other materials Mielewski’s team are reviewing include using shredded U.S. currency as a composite(appropriately) in coin trays, tomato skins from Heinz to make car wiring brackets and storage bins, and hemp fibers in armrests and center consoles.

Deborah Mielewski will be a keynote speaker at the 19th Annual Green Chemistry and Engineering Conference in Bethesda, Md. this July 14-16.

wheatstraw-sm.jpgCELLULOSE-FIBER-COMPOSITE-CONSOLE-ARMREST-sm.jpg

References:

http://corporate.ford.com/microsites/sustainability-report-2013-14/environment-p roducts-materials-choosing.html

 

 

“The Nexus Blog” is a sister publication of “The Nexus” newsletter. To sign up for the newsletter, please email gci@acs.org, or if you have an ACS ID, login to your email preferences and select “The Nexus” to subscribe.

 

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Contributed by Orion Lekos PhD, WSU Extension Biofuel Specialist

 

Biobased Fuels2.png

Advanced Hardwood Biofuels Northwest (AHB) is a consortium of university and industry partners exploring innovative technology using biological and chemical processes to convert poplar into bio-based fuels and chemicals. During the conversion process from poplar wood chips to renewable transportation fuels, intermediate chemicals are produced, including acetic acid, ethyl acetate, ethanol, and ethylene. These bio-based chemicals can substitute conventional petroleum versions to make products that we use in our everyday lives such as paints, plastics, textiles, solvents, and packaging.  Including a portfolio of high-value chemicals is an important piece of a profitable biorefinery. As the price of oil rapidly changes, biofuels are not always cost effective to manufacture.  A biorefinery that can also produce commodity chemicals is more versatile and able to weather the volatile oil markets. The ability to make chemicals at the large scale of a biorefinery also takes advantage of lower operational costs compared to a chemical plant alone. In general, the chemicals made are also more valuable than the fuel and have higher yields, but fuels sell in larger quantities than chemicals and create a stable income for the refinery.

 

 

 

 

 

From one dry ton of poplar chips we get…


Biobased Fuels.jpg


1270 lbs of Sugars

Poplar chips are converted to sugars through hydrolysis where the cellulose and hemicellulose are broken down into glucose and xylose. The sugar can be sold to ethanol producers or it is fermented in AHB’s process to make acetic acid.

 

 

133 Gallons of Acetic Acid

Acetic acid is in high demand globally for the manufacture of paints, ice melting salts, adhesives, polymers, and solvents. From this point the acetic acid can be sold or further processed on to make...

 

 

115 Gallons of Ethyl Acetate

Ethyl acetate a less toxic solvent than acetone used in nail polish remover, cosmetics, perfumes, and to decaffeinate coffee and tea.  Industrially it is made by an esterification reaction of ethanol with acetic acid.  Depending on market demand, the Ethyl Acetate can be sold or further processed on to make...



135 Gallons of Ethanol

The AHB process is nearly 100 % carbon efficient compared to 67% efficiency for traditional yeast fermentation. The ethanol can be sold or further processed on to make...



288 Gallons of Ethylene

Ethylene gas is normally made from petroleum and is a versatile chemical that is the backbone of the plastics we use every. The ethylene can be converted into jet fuel through polymerization.



80 Gallons of Jet Fuel

Two carbon ethylene gas molecules are combined together catalytically to form hydrocarbon fuel chains. This creates a jet fuel made from poplar trees that can be used in existing airplane engines.

 

 

 

 

 

 

 

 

 

 

“The Nexus Blog” is a sister publication of “The Nexus” newsletter. To sign up for the newsletter, please email gci@acs.org, or if you have an ACS ID, login to your email preferences and select “The Nexus” to subscribe.

 

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1386958373440.jpgDr. Richard P. Wool was a familiar and prominent face in the green chemistry and engineering world, whether he was molding the minds of college students, organizing conferences and events (he was until his recent passing a co-chair of the GC&E Conference this year), or conducting award-winning research. His unexpected passing on March 24th has had a huge impact on the green chemistry and engineering community, where he will be remembered by many.

 

Born in Cork, Ireland, Wool received his Bachelors of Science in Chemistry from the University College Cork, Ireland in 1970. After moving to the U.S., Wool received his Masters in Science and Ph.D. in Materials Science & Engineering from the University of Utah. He taught at many institutions before Wool and his family made a permanent home for the past 20 years at the University of Delaware, where he was Professor of Chemical and Bimolecular Engineering. Wool was the director of the Affordable Composites from Renewable Resources (ACRES) program, where he and his students investigated the use of soybean triglycerides as raw materials in the synthesis of new polymers suitable for liquid molding processes.

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In 2011, Wool received the ACS Award for Affordable Green Chemistry for developing uses for bio-based materials like chicken feathers and soybeans to create a diversity of products from roofing and housing materials to circuit boards to a synthetic fabric Wool named “eco leather”.

 

In 2013, Richard Wool won the U.S. EPA’s Presidential Green Chemistry Challenge Award for his work in Sustainable Polymers and Composites. The award is the nation’s most prestigious recognition for excellence in green chemistry research that has the potential for positive impacts in commercial application.  He was also elected as a Fellow of the Royal Society of Chemistry and the American Physical Society, Division of High Polymer Physics.  Wool published over 150 papers, wrote two books, and holds four patents.

 

After being present at many Annual Green Chemistry & Engineering Conferences, including a DSCN0070.JPGkeynote address in 2012, Wool was helping to shape the 2015 conference as a co-chair of the organizing committee.  Dr. David Constable, Director of the ACS GCI, stated “he was extremely supportive and active throughout the past year as a Conference Organizing Committee Co-Chair.  We will greatly miss his leadership, good wit, and strong support.”  A former student, Dr. Joseph F. Stanzione, III, Assistant Professor and Graduate Program Coordinator in the Chemical Engineering Department at Rowan University, has joined the GC&E organizing committee in Wool’s honor.  While Wool will be remembered at the GC&E conference for all he has done to advance green chemistry and engineering, his influence extends well beyond and into the future.

 

 

 

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Contributed by Tim Bugg, Department of Chemistry, University of Warwick, Coventry CV4 7AL, UK.

 

Lignin, the aromatic polymer that binds together cellulose and hemicellulose in plant cell walls, is one of the big unsolved problems in the “biorefinery concept”, whereby plant biomass could be used to provide renewable fuels and chemicals for society and the chemicals industry. While great progress has been made in converting cellulose to cellulosic biofuels, and hemi-cellulose to useful fermentation products, lignin is still the problem child that no one quite knows what to do with. It is produced as a by-product of pulp/paper manufacture, and increasingly produced from cellulosic biofuel manufacture, but it is not susceptible to hydrolytic breakdown, and is a rather inert, insoluble material that is usually just burnt to provide heat. But its content of aromatic rings represents a potential source of renewable aromatic chemicals, so surely we could do something better with it than burning it?

 

Since the 1980’s scientists have studied micro-organisms that can break down lignin, the most active organism being white-rot fungus Phanerochaete chrysosporium, which produces an arsenal of extracellular lignin peroxidase and manganese peroxidase enzymes, with other fungi producing copper-dependent laccases. However, the discovery of these enzymes hasn’t yet translated into a commercial process for conversion of lignin into renewable chemicals, partly because fungal enzymes are hard to over-express in large quantities. Hence there has been renewed interest in soil bacteria that can attack lignin. For many years no bacterial lignin-oxidising enzyme had been identified, but in the last few years several bacterial enzymes have emerged. Members of the dye-decolorizing peroxidase (DyP) family of peroxidases have been identified that have activity for oxidation of lignin and lignin model compounds: DypB from Rhodococcus jostii RHA1 was identified by my research group in collaboration with Lindsay Eltis at UBC, and Michelle Chang’s group at UC Berkeley have identified a Dyp2 enzyme from Amycolatopsis sp. 75iv2. Bacterial laccases are also found, particularly in actinobacteria, and John Gerlt’s group at U Illinois have shown that laccase enzymes in Streptomyces A3(2) are involved in lignin breakdown.

 

Can we use these enzymes as biocatalysts to transform lignin into renewable chemicals? It seems so obvious, and yet, unfortunately, it’s not as simple as that, because the same enzymes that depolymerise lignin also polymerise the radical intermediates formed, generating higher molecular weight material. So you get competing depolymerisation and repolymerisation, in other words, one step forward and two steps back. Somehow Nature appears to solve this problem, we don’t know exactly how at present.

 

So could we use microbial fermentation to transform lignin into chemicals? This approach is starting to yield some interesting results. Although our knowledge of the metabolic pathways for lignin breakdown is very incomplete, there are indications that vanillic acid is one key intermediate in lignin breakdown. In Rhodococcus jostii RHA1, the group of Lindsay Eltis identified the genes responsible for oxidation of vanillin to vanillic acid, and then demethylation to protocatechuic acid, and generated gene deletion strains lacking these genes. When we tested the gene deletion strain for vanillin dehydrogenase, we found that when we grew this strain on minimal media containing chopped wheat straw, we could detect vanillin (for which there is a market in the food/flavour industry) as a metabolite. Under optimised conditions we obtained a yield of 96 mg/litre vanillin, not quite an industrially useful yield, but a big step forward, showing that synthetic biology could in principle be used to generate aromatic chemicals from lignin breakdown. We now hope to use this kind of approach to generate other aromatic compounds for industrial applications, and my group is collaborating with Biome Bioplastics to try to generate products from lignin that could be used to make new bio-based plastics to replace oil-based plastics, as described on:

 

 

There is still a long way to go: we still don’t fully understand the degradation pathways, we know little about how lignin degradation is regulated, and how lignin fragments are taken up into bacterial cells. But that also makes it an interesting area for study, and despite a strong dose of scepticism that I’ve encountered sometimes, I personally believe that it will be possible to convert lignin into renewable chemicals, maybe using biocatalysis, or chemocatalysis, or some combination of the two approaches. Not only do I think it’s possible, but I think we have to find a way to do this, to provide an alternative to petrochemicals for tomorrow’s Society.

 

References

 

Bugg TDH, Ahmad M, Hardiman EM, Singh R (2011). The emerging role for bacteria in lignin degradation and bio-product formation. Curr. Opin. Biotech., 22, 394-400.

 

Ahmad M, Roberts JN, Hardiman EM, Singh R, Eltis LD, Bugg TDH (2011). Identification of DypB from Rhodococcus jostii RHA1 as a lignin peroxidase. Biochemistry, 50, 5096-5107.

 

Brown ME, Barros T, Chang MCY (2012). Identification and characterization of a multifunctional dye peroxidase from a lignin-reactive bacterium. ACS. Chem. Biol., 7, 2074-2081.

 

Majumdar S, Lukk T, Solbiati JO, Bauer S, Nair SK, Cronan JE, Gerlt JA (2014). Roles of small laccases from Streptomyces in lignin degradation. Biochemistry, 53, 4047-4058.

 

Sainsbury PD, Hardiman EM, Ahmad M, Otani, H, Seghezzi N, Eltis LD, Bugg TDH (2013). Breaking down lignin to high-value chemicals: the conversion of lignocellulose to vanillin in a gene deletion mutant of Rhodococcus jostii RHA1. ACS Chem. Biol., 8, 2151-2156.

 

For podcast on lignin degradation see: http://www2.warwick.ac.uk/fac/sci/chemistry/research/bugg/bugggroup/research/lig nin/

 

 

 

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Contributd by Zhiqian Wang and Somenath Mitra*, Department of Chemistry and Environmental Science, New Jersey Institute of Technology

 

Battery Pic.jpgThe development of flexible electronics printed on polymer matrices has opened up the possibilities of mobile phones to be folded into the pockets and a variety of electronic products including flexible displays, smart surfaces (Figure 1) and sensors to be made into different bendable shapes, that can be rolled up, twisted or inserted in films. Thanks to flexible organic LEDs and solar cells, it is possible to have rolled up window shades that have solar cells on one side to generate electricity and TV screen on other side for watching the evening news. Flexible batteries rolled up as carpets can be used for energy storage in solar powered green buildings. Other applications of flexible electronics include the “internet of things” such as sensors that go on food packaging and smart tags.  The market for flexible electronics is expected to go from 24 billion in 2014 to over 70 billion by 2024 (source IDTechEx.com). There is an additional requirement for this new electronic revolution to remain “flexible”, and that is the availability of flexible power sources such as batteries. Typical batteries in the market are AA, AAA, D type and Lithium ion batteries. At present, these batteries appear to be the source of inflexibility and researchers are scrambling to develop flexible batteries.

 

The basic structure of flexible battery being developed in Dr. Mitra’s group at New Jersey Institute of Technology is shown below (Figure 2 a). Like all other batteries, a flexible battery is composed of cathode, anode, separator between the electrodes, current collectors, and packaging materials; the only requirement is that each component must be flexible.

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Figure 2. a) Schematic diagram of a flexible battery; b) a flexible electrode; c) flexible batteries powering LEDs.

 

One of the major challenges in the fabrication of such batteries is the flexible electrodes. Traditional electrodes crack and disintegrate on bending. In order to acquire desired performance and flexibility, polymeric binders along with conductive polymers are often added into the electrode to “glue” the electroactive particles together. The requirements can be stringent: the binder should not dissolve in the electrolyte, and the electrodes should have low electrical resistance, high mechanical strength and high reactivity. Thanks to nanotechnology, there can be many options. For example, when traditional conductive materials like graphite cannot meet the specifications, nanomaterials like carbon nanotubes provide an alternative. These nanocarbons are highly conductive, flexible with high mechanical strength, and are chemically inert. Due to their tiny dimensions, these nanotubes can fill the gaps among electroactive particles to form conductive networks more efficiently than graphite, and hence bring down the electrode resistance dramatically. Certain treatment of carbon nanotubes, like purification, may further improve the performance. Furthermore, composition of additives needs to be optimized to maintain a balance between the battery performance and flexibility.

 

Another consideration in the battery fabrication is the separator, which should be electrically insulating but allow ions to pass through. Besides the structure and packaging considerations, a separator needs to store electrolytes and has special requirements in the case of harsh environment such as in an alkaline cell where the electrolyte is a strong base (KOH). Finally, all components need to be packaged into a compact system with good electrical connections. In general the platform for flexible batteries is quite interesting. Various conventional batteries such as zinc-carbon, primary alkaline, rechargeable alkaline as well as lithium-ions are being fabricated. Conventional screen printing, inkjet printing as well as 3-D printing open the doors to inexpensive manufacture of a variety of these batteries to power electronics and harvest energy at home from flexible solar cells.

 

References:

 

  1. Z. Wang, N. Bramnik, S. Roy, G. D. Benedetto, J. L. Zunino III, S. Mitra. Journal of Power Sources, Volume 237, 2013, Pages 210-214.
  2. Z. Wang, Z. Wu, N. Bramnik, S. Mitra. Advanced Materials, Volume 26, 2014, Pages 970-976.
  3. Z. Wang, S. Mitra. Journal of Power Sources, Volume 266, 2014, Pages 296-303.

 

 

 

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Contributed by Jacques Komornicki, Innovation Manager, CEFIC / Suschem

 

Today, almost 75% of European citizens live in cities and this trend will continue. To succeed in creating sustainable and healthy cities, the Covenant of Mayors was launched in 2008. Currently, 6,279 cities have committed to support Europe’s 20-20-20 objectives of 20% reduction in emissions, 20% renewable energies and 20% improvement in energy efficiency by 2020. The majority of cities have committed to increase energy efficiency by improving buildings, equipment and facilities’ performance and by working with citizens and related stakeholders.

 

The European Community has launched the “Smart-Cities and Communities European Innovation Partnership” which aims to accelerate the development and market deployment of energy efficient building solutions, mobility technologies with lower emissions and energy supply and ICT technologies for smart cities.

 

External wall insulation.jpgThe Chemical Industry is a key supplier of materials and solutions that contribute to the innovations that must be deployed to fulfil these goals. In the European Innovation landscape, the chemical industry works with the European Community within SusChem (the European Technology Platform for Sustainable Chemistry), which gathers together the European Chemical Industry and its stakeholders in academia, Research Technology Organizations and other value-chain players with whom the chemical industry collaborates.

 

In the smart-cities arena, the SusChem stakeholders provide many materials and solutions that can contribute significantly in the deployment of smart-cities; the most important are those related to the energy efficiency of buildings (see below) but there are other contributions such as new materials for use in batteries for Electric Vehicles (an important part of future transportation systems in smart-cities) or photovoltaic panels that can be integrated in buildings.

 

In 2013 SusChem published a comprehensive document: “Innovative Chemistry for Energy Efficiency of Buildings in Smart-Cities." This described a portfolio of innovative material solutions for energy efficiency.

 

1. Reflective indoor coatings

 

By reflecting light better than normal paints, these coatings maximize the feeling of space and illumination. This in turn allows the amount of energy used for artificial lighting to be reduced and/or increases the perceived illumination by natural light.

 

These coatings optimize the use of natural and artificial lighting (increased perceived light up 20%, or 20% energy reduction for the same light perception) and can help keep solar radiation heat inside the building in wintertime. In recent tests, reflective indoor coatings have shown a life expectancy of 5-10 years without losing any performance. The cost of these coatings is only marginally higher than that of 'normal' good quality paints. The effect of using these coatings is highest in climate zones which suffer from limited daylight intensity and duration (Northern and middle Europe).

 

2. High reflectance and durable outdoor coatings

 

High reflectance and durable outdoor coatings applied on buildings’ roofs and walls in hotter climate regions can save up to 15% of air conditioning energy consumption while also allowing for down-sizing of the air conditioning system. Life expectancy of this technology is 12-15 years and up to 25 years for top-of-the-range coatings depending on the climate. Costs of applying these coatings are affordable and offer reasonable payback times. If a roof needs re-painting for maintenance reasons, then choosing a high quality solar reflecting paint is an obvious smart choice especially in sunny, Southern European cities.

 

3. Phase Change Materials (PCM)

 

PCM are available on the market as an active ingredient of a range of semi-finished materials: plaster, cement, plasterboard and multifunctional wall and roof modules as well as films. When used on (interior) walls and/or ceilings, PCM enables them to absorb and store excess heat during the day and dissipate it during the night when air temperatures drop. Essentially PCM increases the thermal inertia of the walls and ceilings. As such, PCM containing walls and ceilings can moderate fluctuations of the indoor temperature, providing an improved comfort and saving energy.

 

PCM has shown life expectancy of 30 years without losing any performance and has demonstrated savings of up to 10% in energy for cooling. The use of PCM also allows downsizing of the air conditioning system and therefore the capital cost.

 

Cavity wall insulation.jpg4. Advanced insulation foams

 

Advanced insulation foams with high insulation performances allow significant energy savings and can be adapted to different building configurations.

 

  • Insulation in wall cavities

 

Cavity wall insulation fills the space (cavity) between the two layers of an external wall of a building. An existing building's wall cavity can be injected with foam as part of an energy efficiency refurbishment. In new construction the cavity is normally filled using rigid pre-foamed panels attached to the wall.

 

  • External insulation

 

There is also the option to insulate the external walls of a building from the outside. This approach maintains the thermal storage capacity (thermal inertia) of the building’s external walls keeping temperature fluctuations at acceptable levels. Each insulation 'stack' is composed according to the specific wall characteristics, climate and orientation of the building.  As well as the thermal insulation performance level, other material selection criteria include fire resistance, mechanical strength, stability, water absorption, permeability and cost. For most applications, the life expectancy of these insulation facade systems is up to 20 years.

 

  • Internal Insulation

 

In case of historical façades, as often found in Europe's older inner cities, buildings can also be insulated from the inside. By applying a layer of high performance insulation foam covered with, for example, plaster or plasterboard, this approach does not alter the external appearance of a building. Obvious disadvantages include a loss of net interior space as well as an effect contrary to that of PCM: by insulating the interior space from the dampening effect of the stone walls, the thermal inertia of the interior is actually reduced, making the interior susceptible to stronger temperature fluctuations. However, it is estimated that high performance foams can reduce energy costs by at least 30%.

 

5. Vacuum insulation panel (VIP) modules

 

Vacuum insulation panel (VIP) modules enable design freedom and allow aesthetical and durable buildings with improved thermal performance. Their insulation performance is up to three times higher than conventional insulation materials. Until recently, VIP were seldom used in buildings due to their fragility and the risk of damaging the vacuum by perforation. However recent products encapsulate the vacuum inside a double glazing package and use amorphous silica foams as the high performance insulation material, allowing their use in glass-dominated (office) building facades that need a significant improvement of their thermal insulation performance.


Impact

 

The combination of these five technologies could result in an overall direct energy savings for heating and air-conditioning of more than 40%. The exact amount of savings will depend very much on the type and location of the building.

 

It is important that these technologies be integrated as part of the global (re)design of the building; for instance a building with issues of thermal bridging will only benefit fully from these high performance materials if such thermal bridges are also addressed during refurbishment. The deployment of these technologies must be achieved within the current construction industry value-chain.

 

Although these technologies can be used for new buildings, they are of particular significance for the refurbishment market of older, high energy consuming buildings which constitute the largest part of the European building stock. Europe is tackling the issue of improving the performances of its building stocks through specific directives that member states will have to translate into national directives.

 

A back-of-the envelope calculation shows that to reach the overall emission targets in 2050, the rate of restoration of buildings will need to be as high as 3% per year. This ambitious target together with the other smart-cities challenges on transportation and energy production and distribution means that not only technical challenges must be tackled but also other challenges related to financing, business models and regulations; all these challenges are being discussed within the European Innovation Partnership “Smart-Cities and Communities”.

 

For more information about SusChem and its solutions for smart and energy-efficient cities, please visit www.suschem.org.

 

 

 

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