(373d) Towards Net-Zero in the Chemicals and Materials Industry: A Systems Approach to Technology Integration, Synergies, and Cost-Effective Decarbonization

The global pursuit of a net-zero carbon economy cannot be realized without transforming the chemicals and materials industry (CMI)—a foundational yet hard-to-abate sector. Products from the CMI underpin modern economies but are responsible for nearly three-fourths of embedded global greenhouse gas (GHG) emissions [1]. In response to this critical challenge, governments, industries, and institutions around the world have issued net-zero pledges aimed at decarbonizing this sector [2]. However, achieving these ambitions remains deeply uncertain in the absence of a unified, systems-level roadmap that integrates both emerging and conventional technologies across the chemicals and materials domains.While recent literature has made progress by assessing promising low-carbon and net-negative solutions—including bio-based manufacturing, electrification, carbon capture and utilization (CCU), and recycling [3, 4, 5]—most studies address these technologies in isolation or focus on limited sub-sectors [6]. Moreover, innovations with lower technology readiness levels are often excluded, and the broader industrial symbiosis between chemical, materials, and fuel systems is seldom considered. Although industry-specific roadmaps exist for various chemicals and materials, each typically addresses pathways to net-zero emissions independently [7, 8]. This siloed perspective risks overlooking cross-sector synergies that could unlock significant gains in emissions reduction and cost-efficiency.

To address these limitations, we develop a comprehensive superstructure optimization model grounded in an open-access dataset of conventional CMI technologies [9]. The Chemicals and Materials Industry encompasses a wide spectrum of production processes, ranging from conventional chemical manufacturing techniques—such as steam cracking, catalytic cracking, and polymer production—to the broader materials sector, including iron and steel, aluminum, cement, glass, paper, and other foundational industries. Given this diversity, our inclusion of both chemicals and materials within a unified framework enables the exploration of potential industrial symbiosis opportunities, where interconnected processes may lead to enhanced resource efficiency and emissions reduction. To capture the full range of decarbonization pathways, we extend the baseline CMI model by incorporating a comprehensive portfolio of alternative value-chain technologies. These include renewable electricity sourcing, electrified production methods, bio-based chemicals and plastics, point-source carbon capture and utilization (CCU), direct air capture (DAC), carbon storage, on-demand transformation technologies, and both mechanical and chemical recycling approaches. Additionally, we account for end-of-life treatment technologies such as plastic pyrolysis and waste incineration for material and energy recovery. In total, the expanded network features over 350 processes and more than 250 products.To ensure robust representation of these interconnected systems, circularity and dynamic emission profiles are incorporated using well-established frameworks from the literature [10, 11, 12, 13], enabling a realistic evaluation of material flows and environmental impacts across the entire network. Technology costs are derived from techno-economic literature and roadmapping efforts, capturing both operational expenditures and innovation-driven investments.Using this model, we investigate a comprehensive set of decarbonization scenarios by systematically analyzing individual technology pathways—such as recycling, bio-based production, electrification, and carbon capture—followed by their pairwise and multi-technology combinations. This stepwise exploration allows us to assess how different combinations of strategies impact emissions and cost outcomes across the CMI. In doing so, we identify high-impact synergies and gain valuable insights into innovation priorities and opportunities for more effective system-wide decarbonization.

Our findings reveal that recycling consistently emerges as a high-impact, cost-effective solution, especially when coupled with electrified processes. Carbon capture technologies, while beneficial, prove viable only in scenarios supported by abundant renewable electricity due to their substantial energy demands. In the chemicals sector alone, a combination of bio-based feedstocks, recycling, and renewables is sufficient to reach net-zero emissions. However, when the materials industry is included, residual emissions persist unless DAC is implemented—demonstrating that even the most aggressive deployment of available technologies may not fully close the emissions gap. This insight underscores the need for deeper system-level integration and an informed innovation strategy. To this end, we perform a detailed exploratory analysis evaluating both emissions-reduction potential and cost-effectiveness across multiple technology pathways. This analysis helps uncover critical emission and cost hotspots within the network and serves as a decision-support framework for prioritizing innovation and investment based on impact and feasibility. We further extend our analysis to include CO₂-to-fuel conversion technologies and assess how tighter integration between the chemicals, materials, and fuels sectors can promote enhanced carbon circularity. To support stakeholder decision-making, we construct marginal abatement cost curves (MACCs) for the entire CMI system. These MACCs offer a stepwise visualization of cost and emissions trade-offs, reflecting not only individual technology performance but also systemic interactions and synergies. Notably, options such as plastic pyrolysis and wind-powered electricity emerge as “win-win” interventions, balancing environmental and economic benefits.

In conclusion, this work addresses one of the grand challenges of the net-zero transition by moving beyond fragmented evaluations toward a holistic, system-oriented roadmap for decarbonizing the chemicals and materials industry. By revealing hidden synergies, identifying key leverage points, and quantifying trade-offs, our findings provide a robust foundation to guide innovation, investment, and policy in the global effort to achieve deep industrial decarbonization.

References:

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[11] Vyom Thakker and Bhavik R. Bakshi. Designing Value Chains of Plastic and Paper Carrier Bags for a Sustainable and Circular Economy. ACS Sustainable Chemistry & Engineering, 9(49):16687–16698, December 2021.

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