Building on the bio-ethanol platform. Plant-based chemicals and materials play an important role in mitigating climate change, allowing recycling of CO2 and supporting the transition from today’s fossil- to a renewables-based economy (IEA report). Companies are increasingly adopting plant-based materials to meet sustainability goals (WSJ article). One notable plant-based chemical is bio-ethanol. With annual global production of ~80 million tons (or ~27 billion gallons), it is by far the largest bio-chemical produced today accounting for >80% of all bio-chemicals production. Using corn and sugarcane, respectively, the US and Brazil are the largest producers of bio-ethanol. Today bio-ethanol is predominantly mixed with gasoline and used as a fuel. With electric vehicles on the rise, demand for bio-ethanol will likely decrease. For New Iridium, this presents an opportunity to repurpose bio-ethanol as a platform feedstock to produce high-value plant-based chemicals and materials to decarbonize the chemical industry.
Plant-based acetic acid from bio-ethanol. At New Iridium, we are developing a highly efficient oxidation process that converts bio-ethanol to acetic acid (Figure 1). Acetic acid (known as vinegar after its main domestic use) has an industrial global market of $15B. Each year, 20 MT of acetic acid is produced and used primarily as an intermediate for downstream vinyl acetate monomer (VAM) and other acetate ester products. VAM is a versatile chemical and key component of many consumer products such as shoes, paints, adhesives, and packaging materials. Our competitive advantage is a differentiated plant-based product that is cost competitive with the fossil-based Cativa process while abating 1.24 kg CO2 per kg of acetic acid produced. Our solution has achieved high process performance metrics including >95% conversion, >95% selectivity and ~400gL-1h-1 space-time yield. For a comparison of space-time yield, our process has ~200X higher productivity than traditional fermentation of ethanol-to-acetic acid and is on par with the incumbent Cativa process that uses methanol and carbon monoxide feedstocks. We have accomplished kg-scale production of plant-based acetic acid using an irradiated bubble column photoreactor (1 ton/y capacity) enroute to scaling up to a 10 ton/y pilot.
Figure 1: Plant-based acetic acid from bio-ethanol.
1st use case: introducing plant-based shoe materials. New Iridium’s plant-based acetic acid plays a pivotal role in decarbonizing the PEVA (or EVA) value chain (PEVA = poly(ethylene-vinyl acetate), Figure 2). PEVA is a copolymer of ethylene and vinyl acetate, where VAM contributes 10 to 40 wt%, with the remainder coming from ethylene. PEVA is an essential material used in footwear such as Allbirds and Crocs, two companies that have pledged to increase plant-based content in their products. Our solution enables 20% bio-content in PEVA with only 5% added cost* while the current bio-ethylene solution results in 15% added cost, or 3X more. At scale, our plant-based acetic acid can achieve cost parity with the incumbent fossil-based Cativa process and will thus be poised to disrupt the $15B market for acetic acid. (*Assumes initial 14% green premium for our plant-based product.)
