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The article discusses the challenges and importance of industrial catalysis in the chemical industry. Catalysis, which includes homogeneous, heterogeneous, and biocatalysis, is widely used in the production of fuels, commodities, polymers, plastics, and pharmaceuticals. However, there is a lack of communication and dissemination of industrial catalytic processes, hindering their further development and leading to duplication of research efforts. The article emphasizes the need for collaboration between academia and industry to create a framework for sharing knowledge and challenges, which would contribute to the broader implementation of sustainable catalysis. The article also highlights the importance of considering solvents, water, and catalysts in the development of more sustainable and efficient catalytic processes. [Extracted from the article]

Biocatalysis can be applied in aqueous media and in different non-aqueous solutions (non-conventional media). Water is a safe solvent, yet many synthesis-wise interesting substrates cannot be dissolved in aqueous solutions, and thus low concentrations are often applied. Conversely, non-conventional media may enable higher substrate loadings but at the cost of using (fossil-based) organic solvents. This paper determines the CO2 production—expressed as kg CO2·kg product−1—of generic biotransformations in water and non-conventional media, assessing both the upstream and the downstream. The key to reaching a diminished environmental footprint is the type of wastewater treatment to be implemented. If the used chemicals enable a conventional (mild) wastewater treatment, the production of CO2 is limited. If other (pre)treatments for the wastewater are needed to eliminate hazardous chemicals and solvents, higher environmental impacts can be expected (based on CO2 production). Water media for biocatalysis are more sustainable during the upstream unit—the biocatalytic step—than non-conventional systems. However, processes with aqueous media often need to incorporate extractive solvents during the downstream processing. Both strategies result in comparable CO2 production if extractive solvents are recycled at least 1–2 times. Under these conditions, a generic industrial biotransformation at 100 g L−1 loading would produce 15–25 kg CO2·kg product−1 regardless of the applied media. [ABSTRACT FROM AUTHOR]

In nature, enzymes conventionally operate under aqueous conditions. Because of this, aqueous buffers are often the choice for reaction media when enzymes are applied in chemical synthesis. However, to meet the demands of an industrial application, due to the poor water solubility of many industrially relevant compounds, an aqueous reaction system will often not be able to provide sufficient substrate loadings. A switch to a non-aqueous solvent system can provide a solution, which is already common for lipases, but more challenging for biocatalysts from other enzyme classes. The choices in solvent types and systems, however, can be overwhelming. Furthermore, some engineering of the protein structure of biocatalyst formulation is required. In this review, a guide for those working with biocatalysts, who look for a way to increase their reaction productivity, is presented. Examples reported clearly show that bulk water is not necessarily required for biocatalytic reactions and that clever solvent systems design can support increased product concentrations thereby decreasing waste formation. Additionally, under these conditions, enzymes can also be combined in cascades with other, water-sensitive, chemical catalysts. Finally, we show that the application of non-aqueous solvents in biocatalysis can actually lead to more sustainable processes. At the hand of flowcharts, following simple questions, one can quickly find what solvent systems are viable. [ABSTRACT FROM AUTHOR]

The combination of deep eutectic solvents (DESs, ChCl/glycerol 1 : 2) with buffer (up to 15 % v/v) leads to solvent mixtures that exert viscosities below 25 mPa s−1 at 45 °C while keeping their non‐aqueous nature. This enables the setup of efficient enzymatic esterifications, which can also be applied in different continuous systems. Following those premises, the use of microreactors in biocatalytic reactions was explored using (low‐viscous) DES‐buffer media, showing that reactions could be performed efficiently. Under non‐optimized conditions, the microreactor devices led to specific productivities considerably higher than those observed in the batch reactor (14 vs. 0.24 mgproduct min−1 mgbiocat−1) at the same enzyme loadings and conversion of 6 % (to assure a fair comparison). Looking beyond, the combination of several microchannels (e. g., in scale‐out fashion) with DES‐water media may lead to powerful, sustainable, and efficient tools for industrial synthesis. [ABSTRACT FROM AUTHOR]