Economic and environmental comparison of one-step and two-step processes for methacrylonitrile production via isobutene ammoxidation
Peer-Reviewed Publication
Updates every hour. Last Updated: 23-Oct-2026 18:16 ET (23-Oct-2026 22:16 GMT/UTC)
Researchers have conducted a comprehensive techno‑economic analysis and life cycle assessment comparing the industrial mainstream one‑step isobutene ammoxidation process with the emerging two‑step route for methacrylonitrile production. Under unified conditions of 99.5 % product purity and 1 t·h⁻¹ isobutene feed, the two‑step process achieves a higher yield of 82.4 % compared with 77.3 % for the one‑step process. However, the one‑step process is superior in unit production cost at 1.90 vs. 2.23 USD·kgMAN⁻¹ and life cycle carbon emissions at 7.42 vs. 9.10 tCO₂‑eq·tMAN⁻¹. Sensitivity analysis reveals that each 1 % increase in the two‑step yield reduces cost by 0.07 USD·kgMAN⁻¹ and emissions by 0.37 tCO₂‑eq·tMAN⁻¹, and a yield of 86.9 % makes it economically and environmentally comparable to the one‑step process.
By pre-programming dense stacking faults into diamond, researchers have created a material that stays ultrahard (140 GPa) yet resists cracking, with toughness improved by 120%. The defects actively respond to crack-tip stress, triggering local phase transformations that absorb energy from the very moment a crack starts. This strategy offers a new path to alleviate the hardness–toughness trade-off in superhard materials.
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A latest study published in National Science Review has resolved inconsistencies in the responses of Western Pacific Subtropical High (WPSH) to greenhouse warming that arise from earlier definitions. The study reports a robust increase in WPSH’s area and intensity, its northwestward expansion, as well as in occurrence of stronger, longer-lasting record-breaking WPSH events under the past and future climate change scenario. These changes imply increasing risk exposure to monsoon rainfall extremes and heatwaves beyond historical experience for human society and communities.
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High‑throughput workflows have revolutionized experimental heterogeneous catalysis by enabling rapid, parallel synthesis and screening of catalyst libraries. This review traces the evolution of high‑throughput technology from manual experiments in the early 1900s to today‘s autonomous, artificial intelligence‑driven platforms that integrate robotics, machine learning, and self‑driving laboratories. The state‑of‑the‑art mode encompasses five key steps: experiment design, catalyst synthesis, catalyst testing and screening, catalyst characterizations, and data handling and analysis. Despite its transformative potential, high‑throughput workflows face critical pitfalls—including gaps between microscale reactor results and industrial performance, pressure limitations, and chemical information disparity in funnel‑shaped screening—that must be addressed to fully realize its promise for rational catalyst discovery.