Bio-polymers, lignin utilisation and update on Polyhydroxyalkanoates ( PHA)
Closing the carbon cycle (Dr Christopher Gürtler, Covestro Germany)
- Amongst the dream of green chemistry, “use carbon as a raw material” stands at the top of the list.
- Use CO2 to make sustainable plastics is a dream come true thanks to the co-work of Covestro with the CAT catalytic center in Aachen Germany. The catalyst is the key and was found after 40 solid years of research. Bayer technology service is making the polyol from CO2 supplied by RWE, the energy supply major in Germany. Then Covestro makes polyurethane foam from this polyol, getting it to react and entrapping CO2 as the backbone of the PU foam.
- Process to make the polyol uses CO2, propylene oxyde, alcohol as a starter, and the catalyst.
- The process is reported sustainable as the study evidenced a 20-30% carbon footprint reduction versus the current PU foam manufacturing process.
- An industrial scale plant is under construction .
- The process is continuously being optimized, with the objective to replace more fossil fuel components by bio-based components. This will give a CO2-POM/pFA based TPU , with a carbon footprint reduced by more than 40% versus the conventional process. Covestro is also pursuing a one pot method to cross linkable CO2 polyols in order to make transparent film for coating applications. Crosslinking of CO2 based materials is a major step forwards, with so far promising results.
- The global polyether market is reportedly close to 3 million tons.
Solvay Epicerol*bio-based building block (Dr Thibaud Caulier, Solvay Belgium)
- Epicerol* is the TM of Solvay’ s epichlorohydrin (ECH) based on glycerol , a by product of oil plant based bio diesel . it is produced in Vinythai Thailand under a JV , Advanced Biochemical Ltd , controlled by Solvay having PTT as partner. The plant is integrated on a site producing PVC, allowing the recycling of the brine produced by the ECH process into the catalysis fluid.
- ECH is the major buiding block of epoxy resins used in many industrial applications as coating and adhesive for carbon fibers; it is also a component of high performance syntetic rubbers.
- Although ECH is in overcapacity globally, Solvay’s Epicerol has a competitive advantage in terms of production cost and a GWP reduction by 60%. It saves 2.5 tons of CO2 emission by ton of ECH produced (certified by Dekra). This competitive advantage allows Solvay to operate its plant close to full capacity whilst the industry at large operates reportedly 60% of the installed capacity.
- Solvay’s strategy is to go down the value chain and participate in partnerships to the development of totally bio-based epoxy, replacing bisphenol A by e.g. lignin derivatives. This is an interesting route , however not delivering a drop-in epoxy resin yet. Another route is Novolac epoxy resins combining Epicerol and Cardanol, a cashew nut oil derivative. An this one is reportedly drop-in and manufactured by Cardolite.
Polyfurfuryl alcohol (PFA) thermosets in biocomposite applications (Dr Hans Hoydonckx, Transfurans Chemicals bvba Belgium)
- Company TFA is the global leader for the production of Furfuryl Alcohol (FFA) with a capacity of 40,000t. Raw material is bagasse from sugar cane grown on its own plantations in the Dominican Republic.
- The Furfural( FF) stream is captured distilling the bagasse juice. The Furfural is shipped to Belgium and transformed into FFA.
- Transfuran is an Innovator in the development of Polyfurfuryl Alcohol (PFA), a liquid thermoset resin with very interesting properties. Viscosity is adjustable and so is temperature (Tg ) . Curing is obtained using complex acid and a multistep curing mechanism.
- PFA is sold under Biorez*and Furolite*brands by Transfurans. It has found applications in fire resistant materials, wood fiber composites and high pressure laminates with textile or kraft paper, to make bio-based trays, tablets and emission free decorative panels for example. It is also used to increase the durability of wood in outdoor construction.
- It has also multiple application in automotive to make sandwich honeycomb isolation panels , taking advantage of a super fast curing time.
Cellulose esters (Eric Fautz , Albis Plastic GmbH Germany)
- Albis is a compounding and distribution company for chemical products and it has acquired TheBayer’s cellulose esters business in 1997.
- Cellulose esters are known since the mid 1800’s and were widely used in the pictures and film copy industry until these went digital.
- Albis dvelopped a fully bio based cellulose ester sold under the Cellidor* brand. It is an amorphous thermoplastic material with high gloss and self polishing effect.
- Thanks to its optical properties , it is used in applications in need of wheather or shock resistance like the famous Swiss Army knife made by Victorinox. Also for anti-static dust free surfaces.
Bio-based materials for medical applications (Dr Gunnar Seide, RWTH Aachen University Germany)
- RWTH is part of “The Institute for bio-based materials”, AMIBM , which is situated on the Chemelot campus near Maastricht in the Netherlands.
- The bio-based materials for the bio- medical market is a development area of particular interest for the Institute. Need is for high performance, hemocompatibility, bioactive and biomimetic features, controlled bio-degradability, and so on.
- The Institute, in partnership with suppliers, hospitals and end-users , designs and test new solutions like coextrusion solution spinning for non wowen engineered tissues, for example non invasive heart valves based on PLA or PGA textiles . the PH of these textiles is lowered by the additivation of micro gels .
- Stent structures made of bio-polymers can also be sprayed in vivo into the cavity requiring the stent. Quite impressive technique providing good results on sheeps so far. Biobased materials therefore allow cell-free implants with an increased efficiency and durability.
Status and outlook of lignin utilization (Pr Dr Antje Potthast, University of Natural Resources and Life Science, Wien)
- Success of use of lignin is heavily dependant upon (a) the softness or brutality of the biomass fractionation process, allowing or not to keep the functionality of the natural polymer, as well as (b) the purity of the lignin obtained; hemicellulose residues are hampering the use of lignin.
- The smartest route is to keep the polymer but change the chemical structure to improve lignin reactivity and better fit the desired application. The structure-property-application relationship needs to be properly defined to allow for an efficient development work. The analysis work is reported as extremely time and resource consuming, what is presented as the reason why resource constrained labs have turned their back to research on lignin. Fast and reliable screening techniques are required to address this major obstacle.
- However, the interest is coming back as current heat value of lignin ( around 100 USD by tons) could be turned into a minimum chemical product value of 1200 USD , the avg price of phenol that functional lignin could replace in wood panel glues to prevent formaldehyde emissions.
- Lignin related Patents emission count per year is just skyrocketing which is a good signal of this renewed interest, even if tangible applications are not very visible yet.
Omno Polymers production and application (Dr Ewelyn Capanena, Renmatix Inc., USA)
- There are Many different lignin types depending upon fractionation process used and the scale at which they can be currently produced
- Renmatix lignin is made using a proprietary supercritical water process brand named Plantrose* in a SuperCritical Hydrolysis reactor ( SCH) in their demo plant. Lignin is sold under the Omno polymers brand . It is chemicals free ( low carbohydrate, sulfur free and low ash) .
- Organosolv lignin is considered by the scientific community and reported in publications as the best lignin available; but Renmatix consider that their SCH lignin matches the characteristics of Organisolv lignin. And, of course, it compares favorably to all other reference lignins, eg Alcell, available on the market, as illustrated by numerous graphs.
- In terms of application development, the priority focus of Renmatix is coatings and adhesives , namely plywood adhesive as a substitute to Phenol Formaldehyde and a 100% biobased epoxy. But also cosmetics.
- Successful partner tests have been made for the manufacturing of thermoplastics and plywood adhesives as replacement of PF. The performance of Omno based adhesive compared to PF is illustrated by numerous charts stemming from an extensive application development work on this high volume application. This market opportunity should be further opened by more stringent legal restrictions of PF adhesive forecasted in Canada, the US and the EU.
Application development of a commercial lignin facility (Dr Eddie Peace, West Fraser Mill , Canada)
- West Fraser is an integrated forest products company focusing on wood products with 7000 employees.
- Hinton Alberta Pulp pilot plant is reportedly producing a commercial grade lignin able to sell in the 1000 USD + range .
- Reference patents are Paleologlou’s issued in 2014-2015. West Fraser scaled-up slowly to obtain and integrate feed back from potential end-users. Then it built the pilot plant in Hinton next to an existing pulp mill. Government support was and still is critical . Focus on high value applications is also critical. The market is not structured yet.
- Next step was to build (commissionning is currently underway) a commercial scale plant with a scale-up factor of 100. Capacity at the end of the ramp-up in porduction will be 30 tons per day or 10,500 t/yr.
- Replacement of PF resin for plywood, OSB , LVL and MDF is a clear immediate target of the proposed commercial plant. Global market for PF resin is 6 million tons per year , of which 1.2 in the US (2013 data) .
- Polyols for bio-based PU is the second target application on the list.
Biobased aromatics from lignin and furans . (Dr Jacco van Haveren, Wageningen UR, The Netherlands)
- Leading research group in the Netherlands with 3 main focuses: furan platform, isohexide platform and sugar biotechnology platform.
- Work on aromatics is reported fundamental to replace fossil fuel chemicals by bio-based ones. Availability of fossil based aromatics is decreasing and the resulting price hike is an incentive to their replacement. FDCA as a biobased alternative to terephtalic acid is a good illustration of the upcoming shift.
- PEF is presented as the next generation polyester.
- Lignin is often mentionned as the next potentially plentiful source of biobased aromatics. However, lignin has complicated and heterogeneous structure.
- Only 2% of the lignin produced in pulp molls is commercially available and useable.
- To valorize lignin, we should work work upstream on the biorefinery concept. This is why the Wageningen lab has been participating to the EU Biocore project with the objective of scanning and rating available biomass pre-treatment and fractionation technologies . As a result, the lab is working on lignin obtained by the organosolv fractionation technology (using organic solvents) that was rated the highest grade by the Biocore project team (www.biocore-europe.org) .
- The lab has also developed a technology to depolymerize the lignin using selective catalytic hydrothermal depolymerization in absence of hydrogen.
- Usage of lignin mixed with vegetable oil as asphalt binder in replacement of bitumen is currently being field tested in Zeeland, a region of the Netherlands. As bitumen will become scarce in the future, this is also an interesting application for lignin.
- In conclusion, lignin is still a bit like the Graal for bio-based aromatics but there is still a long way to go to exploit its potential whilst furans are more accessible in the near term.
The PHA product plateform. (Prof Jan Ravenstijn . JR Consulting )
- The chemicals industry is gradually moving from hydrocarbons to carbohydrates as base platform,
- Of the 78 million tons of plastics used for packaging every year , 8 million tons end up in the oceans. This is 15 tons or the content of a garbage truck every minute. Total Volume floating or in suspension in the oceans amounts to more than 250.000 tons today. If this continues, by 2050 there will be more plastic than fish tonnage in the oceans.
- Going to a circular economy is the recommendation of the UN delivered to the CEOs and governants gathered in Davos in Jan 2016. Thinking directions are that plastics should never become waste but be used as raw materials , as technical or biological nutrients. And that they should be de-coupled from fossil fuels.
- Need complementary innovation efforts for bio-benign plastic packaging to become dominant. The PHA platform is mentionned in the UN report as a good starting point.
- PHB, a member of the family is present in many organisms . It has benisolated and characterized since 1925. Currently 30 companies are in development and manufacturing scale up of PHB.
- PHAs are made of chains of PHBs, long, medium’or short , It ranges from amotphous to highly crystalline. Therefore, there is a full spectrum of property designs available from the PHA platform. Controlled biodegradability, and compatibility with other bio-based chemicals are amongst those properties.
- Applications range from compostable bags , the biggest sales volume of a total of 2000 tons per annum currently produced, to parts produced via injection moulding ot additive manufacturing / 3D printing.
- Too few PHA grades have been food contact approved to be used as blown food films. The availability of more food grades should help boost the market potential. Cost performance benefits will be determinant for the adoption of PHA by converters.
- Main players for PHA are: Bio-0n (Italy) Metabolix (USA) , Tera Vêrdae, Newlight Technologies, Kaneka (Japan)
- They all mended powerful alliances with suppliers (eg Bio-On and Cristal Union) and end-users ( eg Newlight Technologies and Ikea.)
- Price per pound of compouded PHA is regularly decreasing to a promised level’of 0,62 USD per pound by 2020.It is expected to level around 1€ a kg for large market access beyond 2020. Currently, capacity is by far in excess of demand as PHA has been a techno push rather than a market pull during the last 15 years. Sales Volumes are reportedly picking up, specifically in Europe for shopping bags under the influence of legislation banning non- compostable shopping bags.
- The after use value chain must also be developped to contribute to PHA attractiveness.
Application development of PHA. (Dr Kevin O.Connor .Bioplastech Ltd UK.)
- PHA is a difficult animal to work with.
- Bioplastech focuses on polymer processing improvement (fermentation process productivity ) and applications of PHA-PLA composites to obtained the desired elongation , tensile strength and barrier properties , reportedly down to 9 cc/sqm/24h ( at which temp was not mentionned) .
Market development of biopolymer Aonilex*. (Kenichiro Nishiza and Takahiko Sugaya. Kaneka Japan.)
- Polymer chemistry and life science are the two core business of Kaneka with 8500 employees throughout the world. Soda, PVC and PVC modifiers , PS and EPS, plant oil based lubricants and plastics are amongst Kaneka.s wide product range as well as food additives and life science products and synthetic fibers.
- Kaneka developped a specific PHA copolymer as new business venture combining oil processing technology, biotechnology and polymerization technology. It is sold under the trade name Aonilex. It is using palm oil as raw material and a fermentation process using micro organisms to produce the desired polymer, a PHBH type.
- Aonilex has reportedly excellent biodegradability in aerobic and anaerobic conditions. It has been firstly used as mulch film and organic waste bags in Japan. A sales office has been recently opened in Belgium’to take advantage of the market pull in the EU linked to the ban of non compostable shopping bags and to the adoption of organic waste collection bags being gradually deployed by member states.
- Sea water disintegration of Aonilex is emphasized: 100% after 300 days at 23°C. Marine degradable applications are amongst the ônes targetd by Aonilex.
Fire resistant bio-composite. (Miguel Angel Valera Gomez . Aimplas Spain.)
- Aimplas is a research center selling polymer processing formulae and optimization advice and assessment services to its clients.
- Project underway to develop PHB and succinic acid ( and subsequently PBS ) from the 32% sugars contained in the SSL available as by-product from the pulping process.
- Aimplas developped the compounding process and scaled it up to 400 kg/h.
- Then the extrusion process was scaled up for sheets up to 600 micron thick and up to 500 mm in width.
- These sheets were then used to make Multilayer sandwich fireproof pannels entrapping a filler. These are manufactured and sold by Solaris Urbino for the automotive industry.
- Compostability was assessed according to EN13432 . The pannel are fully biodegradable but need grinding prior to industrial composting as they do not pass the desintegration test.
PLA-PHA blend based heat-resistant reuseable drinking cups.( Eva Sykacek. University of Natural tesources and Life Science Vienna.)
- The bio-based bio-degradable cup to be developped needed to resist dish washing temp of 75°C and have a material cost < 3.5€/kg (excluding compounding cost).
- A blend of PLA3251D from Natureworks and Mirel PHA 1006F was used , both component being injection molding grades. Chalk was added in the blend as a mineral’filler to reduce the material cost . Experimental design was used to reduce the number of runs to 12. Each allowed to find the optimum composition to maximize the values of the desired features eg tensile strength.
- The suitable blend was found to be 19% PLA, 61 % PHA and 20% chalk and it delivers 3,11€/kg as a raw material cost, within target. Heat distorsion temperature is 75,5°C also within target. Real dish washervtesting confirmed the suitability /reuseability.
- The experimental method used proved to be very efficient to rapidly find the suitable blend .
Levulinic acid as a feedstock for bio-based bio-degradable polymers. (Alexander Krapivin .GFBiochemicals Ltd. the Netherlands.)
- GFBiochemicals is the first company to produce levulinic acid directly from biomass at commercial scale, from a production site in Italy.
- Levulinic acid is a versatile platform molecule with multiple usage . GFB is puttingbtogether strategic partnerships for the downstream’production of esters and ketals .
- Levulinic acid has been proven as a co-feed with several micro organisms tô produce PHAs. It actually boosts PHA polymer properties and enlarge the processing window thanks to the presence of 4HV groups. Levulinic acid at 4 to 6g per liter combined with 20g per liter of glucose delivers the maximum yield and presence of 4HV groups ( 3.5 mol%).
- GFBiochemicals bio-based plasticizers, levulinic acid ketals, ( ex-Segetis), are also enhancing PLA properties. The same is applicable to WPC/ Wood Plastic Composites and PVC.
Improving versatility of polymers using Metabolix PHA copolymers (Anindya Mukkherjee, consultant to Metabolix Inc USA)
- Metabolix started in 1992 as a spin-off from the MIT.
- They pivoted to Specialties after an initial commercialization phase of plain PHA for commodity type applications such as packaging
- Their PHA biopolymer portfolio is based on industrial sugars and non food plant oil as raw materials.
- They are FDA approved for food contact .
- They developped extended PHA technology to enable amorphous PHA grades (aPHA) and market them in blends with PLA to obtain remarkablé properties, eg improved flexibility w/o lowering the Tg of PLA, or increased toughness of injection molded products or tenterframe PLA sheet .
- aPHA (i6002 grade) has also been proven to improve the tensile strenght of flexible PVC and reduce the extrusion machine torque for WPC formulations (i6003 grade)
- In conclusion, aPHA is a bio-based additive that enhance performance of multiple bio-based or non bio-based polymers, opening a full new field of applications to the PHA platform, which is somehow in desperate need of it and of the opening of the market after 15 solid years of struggle.
- Let’ finish the report of those two days of extremely interesting presentations and contacts on this very positive tune!