There is no denying that plastics represent an integral part of our technological, consumer and recreational lives. Cheap to produce and highly versatile, plastics can be moulded, pressed, squeezed and shaped into just about any form, and for any purpose. We are all familiar with plastics that make up the packaging that keeps our foods, drinks and toiletries safe, and with the durable, colourful plastic toys that our children play with, but these ubiquitous materials are also used to make lifesaving medical equipment and instruments, weatherproof clothing, and even bulletproof vests.
So what are plastics?
The term plastics comes from the Greek word ‘plastikos’, which means suitable for moulding, and actually refers to the huge range of synthetic materials. Most plastics are polymers. These are made up of small organic molecules that join together into long chains. The final properties of any polymer – such as heat resistance or how soft or stretchy it might be – will depend on chemical composition of the individual units, or monomers, as well as the length of the polymer chains, and how these chains interact with each other.
Polyethylene terephthalate; PET, is a kind of polyester, and one of the most widely manufactured plastics around the world. In its different forms the polymer is used to make a huge range of goods, including food packaging. We are probably familiar with the names of other common plastics, such as polystyrene, and polyvinyl chloride (PVC).
The majority of plastics today are manufactured from fossil fuels such as crude oil and coal, but scientific advancements over recent years have made it possible to produce plastics from sustainable, plant-derived sources, or feedstocks, including sugarcane, potato starch, cellulose (wood), corn, soy, waste vegetable oil, and other food and farming waste. Chemical and process engineers around the world are developing methods for producing these biobased polymers and plastics that can replace materials made from fossil fuels. Today, many polymers that can be manufactured from renewable feedstocks have identical properties to their fossil fuel-derived counterparts, and may be completely biodegradeable and recyclable.
Alternative routes for bioplastics manufacture
Industrial organizations, materials scientists and public and private groups are exploiting developments in ‘white’, or industrial biotechnology, to optimize processes that can be harnessed to develop energy-efficient, resource-saving methods for sustainable, greener bioplastics manufacturing.
Here are just a few examples:
- A team at the University of Bath in the U.K. has developed a method for manufacturing completely biodegradable microbeads from cellulose.
- The EU-funded EUROPHA project is developing 100% natural, biodegradable polyhydroxyalkanoate (PHA-based bioplastics) for food packaging applications1.
- Mexican biopolymers firm Biofase, makes bioplastic straws and cutlery out of avocado seeds, as an alternative to throwaway products made from petrochemicals.
- New York-based Ecovative Design has developed technology that harnesses fungi to grow biobased plastic alternatives that can be made into a wide range of products, from insulated jackets, technical wear and footwear, to sponges for applying cosmetics.
- GC Innovation America is part of Thailand-based chemicals company PTT Global Chemical Public Company Ltd, which is developing biobased chemicals, including biopolymers, using succinic acid derived from renewable sources.
- French startup Lyspackaging produces the Veganbottle, a 100% vegetable-based, compostable alternative to conventional petroleum-based plastic water bottles, 200,000 tonnes of which are not recycled every year in France alone.
Estimates suggest that while bioplastics currently represent about 1% of the total amount of plastics produced globally every year2, capacity for bioplastics production is on the increase, and the global market for bioplastics biopolymers, which was about $6.95 billion in 2018, could reach $14.92 billion by 20233.
Public funding is critical for supporting innovation in the field. At the end of 2018 the U.K. government pledged £60 million to support the development of sustainable methods for converting farming, food and industrial waste into environmentally friendly packaging4. The EU is similarly funding a range of initiatives, including the development of processes for turning sugarcane waste into biopolymers for fire-resistant applications, and bioplastics that can be formed into 100% compostable food packaging5.
Bioplastics are closing the loop
New processes for converting biomass into biopolymers and bioplastics rely on efficient, reliable technologies and process equipment. As a global leader in white biotechnology, GEA is at the forefront of the field, and has been working with the bioplastics sector for more than a decade to develop, test and fine-tune equipment and technologies that make it possible for industry to scale up R&D and pilot processes into viable commercial manufacturing streams.
Specialists at GEA combine detailed knowhow for key stages of manufacturing, including the use of biobased intermediate compounds, such as succinic acid, that provide alternative routes for bioplastics manufacture. Another example is the production of lactic acid from plant-based sources. Lactic acid is used to manufacture polylactic acid (PLA), a biodegraeable, sustainable alternative to PET, and one of the most commonly produced bioplastics globally.
GEA engineers can custom-design systems for upstream and downstream process stages in the manufacture of intermediates and biopolymers. The GEA portfolio spans solutions for fermentation, and biomass separation using centrifuges or membrane filtration, together with technologies for purification by distillation, melt crystallization or membrane filtration, and for downstream processes including concentration, crystallization, and drying of the final product.
GEA is also part of the €14 million EU-funded PRODIAS initiative, through which eight organizations across Europe are working to develop sustainable technologies that will take down the cost of producing renewable alternatives to fossil fuel-based products6.
Importantly, GEA works with organizations to address process issues and improve efficiency, and help to turn innovative concepts into viable industrial processes for manufacturing bioplastics and other biobased products. Each solution is designed to help save energy and water use, recycle excess heat, and reduce waste and emissions where possible, so that sustainable processes are carried out using sustainable technologies.