Bio-Based Polyisoprene Can Mitigate Climate Change and Deforestation in Expanding Rubber Production

Abstract

Biomass is a promising renewable feedstock to produce polyisoprene for the rubber industry. Through metabolic engineering, sugars derived from pretreated and hydrolyzed cellulose and hemicellulose can be directly fermented to isoprene to produce rubber. Here we investigate the life cycle environmental impact of isoprene fermentation to produce bio-polyisoprene from agricultural residues (of Zea mays L.). Results show that the greenhouse gas (GHG) intensity of bio-polyisoprene (−4.59 kg CO2e kg−1) is significantly lower than that of natural rubber (Hevea brasiliensis) and synthetic rubber (−0.79 and 2.41 kg CO2e kg−1, respectively), while supporting a circular biogenic carbon economy. We found the land use intensity of bio-polyisoprene to be 0.25 ha metric ton−1, which is 84% lower than that from rubber tree plantations. We compare the direct fermentation to isoprene results with indirect fermentation to isoprene through the intermediate, methyl butyl ether, where dehydration to isoprene is required. The direct fermentation of isoprene reduces reaction steps and unit operations, an expected outcome when employing process intensification, but our results show additional energy conservation and reduced contribution to climate change. Among the ReCiPe life cycle environmental impact metrics evaluated, air emission related impacts are high for bio-polyisoprene compared to those for natural and synthetic rubber. Those impacts can be reduced with air emission controls during production. All other metrics showed an improvement for bio-polyisoprene compared to natural and synthetic rubber.

A sustainable aviation fuel pathway from biomass: life cycle environmental and cost evaluation for dimethylcyclooctane jet fuel

“…While the focus of this study is the techno-economic and life cycle GHG emission impact of DMCO jet fuel, multiple other life cycle impact assessment (LCIA) metrics that affect human health and the environment are critical for investment decisions. Our previous research 84 evaluated nine midpoint LCIA metrics using ReCiPe 2016 (ref. 85) for a biorefinery producing isoprene, corresponding with all cradle-to-isoprene process steps in the DMCO life cycle, including the lignin-fed boiler, which was the source of elevated air particulate matter (PM2.5), an indicator of air quality, and slightly high terrestrial acidification, which is also attributed to the lignin boiler.…”

“…85) for a biorefinery producing isoprene, corresponding with all cradle-to-isoprene process steps in the DMCO life cycle, including the lignin-fed boiler, which was the source of elevated air particulate matter (PM2.5), an indicator of air quality, and slightly high terrestrial acidification, which is also attributed to the lignin boiler. Batten et al 84 used the biorefinery mass balance audit from an Aspen Plus simulation by Humbird et al 62 to predict air pollutant emissions for a corn stover-to-ethanol biorefinery that was not equipped with air pollution controls. However, as noted in an earlier analysis by Spatari et al , 86 a biorefinery would not be permitted to emit uncontrolled VOC, CO or NO x emissions and would be required to invest in air pollutant controls, which would raise capital costs, and possible air quality impacts could be mitigated.…”

"Biological Solutions: Catalyst for the Sustainability Transition of the Palm Oil Industry"

“…In terms of benefit, researchers suggested that bio-based polyisoprene is able to significantly reduce greenhouse gas emissions by close to 300% as compared to synthetic rubber. In addition, land use intensity of bio-based polyisoprene is 84% lower than that from rubber tree plantations [23].…”

“…The market of isoprene is estimated to be approximately 4 billion USD by 2025, growing at a compound annual growth rate more than 5% [22]. Today, bio-based polyisoprene is experiencing higher demand due to increase in awareness of sustainability and climate issues resulting in major tire companies like Michelin, Bridgestone and Goodyear choosing to partner with biotech companies to seek alternatives for isoprene supply [23]. In this regard, biological solutions could reduce future dependence on petroleum and is expected to contribute reducing carbon dioxide, widely considered to be a cause of global warming.…”

LCA as a Tool to Detect Environmental “Hot Spots” in Early-Stage Mechanochemical Synthesis of Organic Dyes

“…The categories within ReCiPe allow comparing key global environmental, resource consumption, and human health ecosystem impacts of the two alternative production routes. The ReCiPe 2016 hierarchist method has been widely used to evaluate and benchmark multiple chemicals and production routes, prospective water infrastructure, treatment recovery processes, , emerging biochemicals and biopolymers, and renewable energy materials, processes, and planning. , …”