Quantitative Sustainability Assessment of Flow Chemistry–From Simple Metrics to Holistic Assessment

Abstract

Flow chemistry has changed chemical process designs toward process intensification and is generally considered as green methodology. In this connection, this perspective provides a more critical and holistic view about the sustainability of flow chemistry by introducing both simple and complex holistic tools for environmental quantitative assessment on sustainability and providing examples of how they were used for flow chemistry. The latter also shows a critical assessment of what flow chemistry can add to make chemical processes more sustainable. With the increasing complexity of assessment, green chemistry metrics, life cycle assessment methodology, and circular transition indicators are discussed. In this way, the sustainability of flow chemistry is assessed first on the level of a reaction only and then moving to a process level and beyond. Flow chemists are very aware of the principles of green chemistry and their simple metrics. Yet, they hardly use life cycle assessment, and quantitative circularity analysis has not been made. When those assessments are used, it is usually done by researchers with an ecology background. This perspective aims to make flow chemists aware of the opportunities that complex environmental assessment can provide and that protecting our planet requires a holistic sustainability consideration. The perspective critically states what each of the three types of assessments can do and what their limitations are.

Biocatalytic Production of 2-α-d-Glucosyl-glycerol for Functional Ingredient Use: Integrated Process Design and Techno-Economic Assessment

“…The E -factor (mass waste to mass product) and PMI (total mass to mass product) were thus 28 and 146, respectively. 3 , 45 We also considered to omit the recycling of the glycerol, since its concentration is an energy intensive process (≥628 MW h a –1 ). Stream 12 is thus not recovered but treated as a waste.…”

“… 1 , 2 Integration involves coordination and interconnection of process steps not only to enable efficient production of the desired compound but also to recover side streams for further utilization. 3 While individual process steps are often analyzed in minute detail, less attention is paid to the crucial point of integration. Since individual process steps can have profound influence on each other, their assembly into a complete process requires careful assessment in an interactive process network type of approach.…”

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Mapping Recyclability of Industrial Waste for Anthropogenic Circularity: A Circular Economy Approach

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Life Cycle Assessment of an Enzymatic Ibuprofen Production Process with Automatic Recycling and Purification

“…and outputs (i.e., global warming, waste generations, etc.) as well as the related potential environmental impacts of the pharmaceutical products . Importantly, LCA is internationally accepted as a standard method to evaluate the environmental impact of a chemical or pharmaceutical process by the International Organization for Standardization (ISO) .…”