An Efficient and Practical System for the Synthesis of N,N‐Dimethylformamide by CO₂ Hydrogenation using a Heterogeneous Ru Catalyst: From Batch to Continuous Flow

Abstract

In the context of CO2 utilization, a number of CO2 conversion methods have been identified in laboratory‐scale research; however, only a very few transformations have been successfully scaled up and implemented industrially. The main bottleneck in realizing industrial application of these CO2 conversions is the lack of industrially viable catalytic systems and the need for practically implementable process developments. In this study, a simple, highly efficient and recyclable ruthenium‐grafted bisphosphine‐based porous organic polymer (Ru@PP‐POP) catalyst has been developed for the hydrogenation of CO2 to N,N‐dimethylformamide, which affords a highest ever turnover number of 160 000 and an initial turnover frequency of 29 000 h−1 in a batch process. The catalyst is successfully applied in a trickle‐bed reactor and utilized in an industrially feasible continuous‐flow process with an excellent durability and productivity of 915 mmol h−1 gRu−1.

Highly Efficient and Selective N‐Formylation of Amines with CO2 and H2 Catalyzed by Porous Organometallic Polymers

“…Therefore, the design and fabrication of robust porous catalysts based on viable homogenous catalysts with a large specific surface areas may accelerate the adsorption of CO 2 /H 2 and facilitate the mass and heat transfer, thus leading to a significant enhancement of TONs, especially for the desired DMF synthesis. During our manuscript preparation, Yoon realized the hydrogenation of CO 2 to DMF under 80 atm pressure at 140 °C with TON up to 160 000, by using a ruthenium‐grafted biphosphine porous polymer [14] . However, owing to the air and moisture‐sensitive nature of the Ru‐biphosphine motif and the randomly grafted Ru on the polymer matrix, the yield (80 %) and selectivity were not very satisfactory (along with formic acid as byproduct), and the catalyst could only be reused for 5 runs even at high catalyst loadings.…”

Recent Progress in Continuous‐Flow Hydrogenation

“…Another example of CO 2 conversion into value‐added chemicals involved the production of N , N ‐dimethylformamide ( 103 ) through flow hydrogenation of CO 2 , reported by Yoon and co‐workers . The authors developed a Ru‐grafted bisphosphine‐based porous organic polymer (Ru@PP‐POP).…”

From ‘Gift’ to gift: producing organic solvents from CO2

“…Very recently, an efficient heterogeneous catalytic system for DMF synthesis by hydrogenation of CO 2 was established by Yoon and co-workers, 72 which employed ruthenium-grafted bisphosphine-based porous organic polymer (Ru@PP-POP) as a recyclable catalyst. In a batch process, a TON of up to 160 000 was obtained and excellent productivity and durability were observed in a continuous-flow process, thus offering great potential for industrial application of CO 2 hydrogenation for DMF production.…”