Chemical production is set to become the single largest driver of global oil consumption by 2030. To reduce oil consumption and resulting greenhouse gas (GHG) emissions, carbon dioxide can be ...captured from stacks or air and utilized as alternative carbon source for chemicals. Here, we show that carbon capture and utilization (CCU) has the technical potential to decouple chemical production from fossil resources, reducing annual GHG emissions by up to 3.5 Gt CO₂-eq in 2030. Exploiting this potential, however, requires more than 18.1 PWh of low-carbon electricity, corresponding to 55% of the projected global electricity production in 2030. Most large-scale CCU technologies are found to be less efficient in reducing GHG emissions per unit low-carbon electricity when benchmarked to power-to-X efficiencies reported for other large-scale applications including electro-mobility (e-mobility) and heat pumps. Once and where these other demands are satisfied, CCU in the chemical industry could efficiently contribute to climate change mitigation.
Mitigating life-cycle greenhouse gas emissions of plastics is perceived as energy intensive and costly. We developed a bottom-up model that represents the life cycle of 90% of global plastics to ...examine pathways to net-zero emission plastics. Our results show that net-zero emission plastics can be achieved by combining biomass and carbon dioxide (CO
) utilization with an effective recycling rate of 70% while saving 34 to 53% of energy. Operational costs for net-zero emission plastics are in the same range as those for linear fossil-based production with carbon capture and storage and could even be substantially reduced. Realizing the full cost-saving potential of 288 billion US dollars requires low-cost supply of biomass and CO
, high-cost supply of oil, and incentivizing large-scale recycling and lowering investment barriers for all technologies that use renewable carbon feedstock.
CO2 conversion covers a wide range of possible application areas from fuels to bulk and commodity chemicals and even to specialty products with biological activity such as pharmaceuticals. In the ...present review, we discuss selected examples in these areas in a combined analysis of the state-of-the-art of synthetic methodologies and processes with their life cycle assessment. Thereby, we attempted to assess the potential to reduce the environmental footprint in these application fields relative to the current petrochemical value chain. This analysis and discussion differs significantly from a viewpoint on CO2 utilization as a measure for global CO2 mitigation. Whereas the latter focuses on reducing the end-of-pipe problem “CO2 emissions” from todays’ industries, the approach taken here tries to identify opportunities by exploiting a novel feedstock that avoids the utilization of fossil resource in transition toward more sustainable future production. Thus, the motivation to develop CO2-based chemistry does not depend primarily on the absolute amount of CO2 emissions that can be remediated by a single technology. Rather, CO2-based chemistry is stimulated by the significance of the relative improvement in carbon balance and other critical factors defining the environmental impact of chemical production in all relevant sectors in accord with the principles of green chemistry.
Chemicals manufacture is among the top greenhouse gas contributors. More than half of the associated emissions are attributable to the sum of ammonia plus oxygenates such as methanol, ethylene glycol ...and terephthalic acid. Here we explore the impact of electrolyzer systems that couple electrically-powered anodic hydrocarbon-to-oxygenate conversion with cathodic H
evolution reaction from water. We find that, once anodic hydrocarbon-to-oxygenate conversion is developed with high selectivities, greenhouse gas emissions associated with fossil-based NH
and oxygenates manufacture can be reduced by up to 88%. We report that low-carbon electricity is not mandatory to enable a net reduction in greenhouse gas emissions: global chemical industry emissions can be reduced by up to 39% even with electricity having the carbon footprint per MWh available in the United States or China today. We conclude with considerations and recommendations for researchers who wish to embark on this research direction.
With the increasing global concern over plastics' environmental and human health impacts, the urgency for effective regulatory measures is evident. The UN Environment Assembly's initiative to ...establish an international, legally binding instrument via the Intergovernmental Negotiating Committee (INC) on Plastic Pollution marks a significant step toward addressing this issue. However, the vast diversity of plastic types and their myriad applications present a complex challenge in pinpointing the most critical targets for regulation. This study builds on the existing body of literature to outline potential key criteria for identifying Polymers of Concern (PoC). We recommend a dual-focused definition of PoCs considering both (1) the type of the plastics and (2) their domain of applications based on the environmental and human health impacts throughout the polymer's life cycle. Recognizing the current gaps in our understanding of the full spectrum of plastics' impacts across their life cycles, we suggest adopting a precautionary approach that factors in the volume of plastics entering natural ecosystems alongside their life cycle impacts as reported in the literature. We then bring forward existing data on the assessment of some of the main polymer types and applications. We propose that policymakers examine a wide spectrum of strategies including not only bans and phaseouts but also economic incentives, innovation, and the redesign of plastic materials and products to mitigate the adverse impacts of PoCs. We further emphasize the importance of thoroughly assessing the feasibility, costs, and environmental, social and economic implications of alternative materials to avoid “regrettable substitution.” We conclude by identifying existing knowledge gaps and emphasizing the need for further research to refine the proposed criteria for identifying PoCs.
Plastic packaging waste faces increasingly stringent sustainability targets such as recycling rates of 55% imposed by the European Commission. To realize the vision of a circular economy, chemical ...recycling is advocated as a large-scale avenue to decrease fossil resource depletion and greenhouse gas (GHG) emissions. In this work, we develop a theoretical model for chemical recycling technologies assuming ideal performance. The theoretical model allows us to compute the minimal environmental impacts for chemical recycling technologies and compare them to real-case benchmark waste treatments. Thereby, we robustly identify chemical recycling technologies that will not result in environmental benefits, since their minimal environmental impacts are already higher than those of current benchmark waste treatments. In this way, we show that PET, HDPE, LDPE, PP and PS should not be recycled chemically to refinery feedstock or fuel products and rather be treated by mechanical recycling and energy recovery in cement kilns in order to reduce global warming impacts. In contrast, chemical recycling to monomers or value-added products could potentially reduce global warming impacts compared to all benchmark waste treatments by up to 4.3 kg CO2-eq per kg treated PET packaging waste. By analyzing 75 waste treatment scenarios for 5 environmental impacts, our analysis offers guidance to stakeholders involved in chemical recycling to identify the most promising as well as the least promising chemical recycling technologies.
Display omitted
•Carbon pricing similar to social carbon costs incentivizes net-zero chemicals & plastics.•Capital intensity of net-zero is in the range of current low-carbon investments.•Total annualized costs of ...net-zero production are similar to fossil production.•Recycling is a key to reducing resource demands and sensitivity to resource prices.
Without disruptive change, greenhouse gas (GHG) emissions from fossil production of chemicals and plastics will double by 2050. The transition to net-zero GHG emissions requires a concerted strategy for the whole chemical industry due to its integrated supply chains. A cost analysis is needed to determine the required investments and to design carbon-pricing incentives. Here, we present cost-optimal investment pathways for the global production of chemicals and plastics by using a bottom-up process model that captures the complexity of the chemical industry. To accomplish net-zero, capital expenditures need to increase by 36-51 % over the next 30 years. In contrast, the total annualized cost could be similar (+4 %) to fossil-based production. Net-zero production and its costs will rely on the availability of renewable electricity and biomass. At the same time, high recycling rates are a key to keeping resource demands low and reducing the sensitivity to high resource prices.
Bio-based chemicals are seen as a potential stepping-stone towards a more sustainable chemical industry. However, while bio-based routes are already available for various organic alcohols and acids, ...the direct bio-based production of aromatic compounds has been difficult so far. Recently, the first bio-based process for the production of the important aromatic aniline has been realized. The process produces bio-based aniline via two-stages: first, sugar is fermented by Corynebacterium Glutamicum to aminobenzoic acid, which is then catalytically decarboxylated to aniline. In this study, we present a prospective Life Cycle Assessment for bio-based aniline production to evaluate the environmental potential compared to fossil-based aniline production. Our results suggest that the bio-based production could reduce the global warming impacts of aniline from cradle-to-grave by 35–69% relative to fossil-based production, depending on the type of biomass feedstock. However, bio-based aniline could also substantially increase eutrophication and acidification, a trade-off commonly observed for bio-based processes. Thus, the novel production route is promising and expands the scope of bio-based chemicals towards aromatics.
Display omitted
•First Life Cycle Assessment of bio-based aniline production.•Bio-based production chain in three world regions considering four feedstocks.•Significantly lower global warming impacts possible by bio-based aniline.•Reduced global warming impacts robust regarding indirect land-use change.•Feedstock demand for global aniline demand could be satisfied.
•Myopic decisions delay low-carbon investments and thus cause 43 % more GHG emissions.•Myopic investments add 307 bn-USD of fossil assets, potentially stranded past 2050.•The impact of myopic ...decision-making is more severe on GHG emissions than costs.•Myopic decisions increase costs and GHG emissions for all technology pathways.
Rapid demand growth would double GHG emissions of fossil-based chemicals and plastics production by 2050. In contrast, recycling, biomass utilization, and electrification enable pathways to net-zero GHG emissions. Such pathways often compare the costs of fossil and renewable technologies based on the next 30 years. However, this assumption contrasts the timeframes of legislative periods and investors desiring fast returns, leading to myopic (i.e., short-term) investment decisions. Therefore, this study compares pathways based on long-term with myopic decision-making. While a 20-year foresight still achieves net zero by 2050, a 10-year foresight fails the net-zero target and increases cumulated GHG emission by 43%. Moreover, the chemical industry would invest +307 bn-USD (+3.2%) in additional fossil and, thus, potentially stranded assets. Therefore, industry and investors should account for the environmental and economic impacts of myopic decision-making and practice long-term decision-making to mitigate carbon lock-ins, stranded assets, and financial risks for investors.
PDF
