Transfer of an Agrochemical Process to a Two-Phase-Operated Jet Loop Reactor using the X-Scaling Approach

In the chemical industry, process intensification is often pursued to enhance efficiency and sustainability. This work contributes to such efforts by presenting the fundamental concept and an application of the novel X-Scaling approach, which enables the transfer of an established agrochemical process from traditional bubble columns to an alternative jet loop reactor system. The approach involves extensive experimental investigations across different scales using both a simple water–air system and an industrially relevant reactive system to facilitate the desired process transfer. The primary objective is to overcome mass transfer limitations previously identified in the existing bubble column process, which resulted in long residence times and unconverted gaseous reactants in the exhaust stream. To improve gas–liquid mass transfer, the process is intensified by increasing the specific interfacial area while maintaining a mechanically simple and low-maintenance reactor design. A two-phase jet loop reactor is therefore chosen to replace the current three-stage bubble column cascade. This reactor offers improved mass transfer performance, simpler scalability, and enables more efficient use of raw materials with reduced environmental impact. A laboratory-scale reactor was designed based on data from the industrial process and a pilot reactor, maintaining geometric similarity, constant specific energy dissipation, and volumetric gas flow rates. Both laboratory and pilot reactors were characterized using a water–air system to determine scale-independent correlations. The results confirm that the jet loop reactor concept can be reliably transferred between scales and provides a broad operational window. Critical aspects identified during reactor characterization include pressure drop in the two-phase nozzle and accumulation of gaseous by-products, which affect process selectivity. To address these, the Gas Residence Time Method was developed, implemented, and validated using optical techniques. Additionally, a gas sparging device was designed to remove absorbed by-products and to support stable loop flow within the reactor. Overall, this research contributes to the development of more sustainable and resource-efficient processes in the chemical industry. It demonstrates the applicability of the jet loop reactor for process intensification and introduces the X-Scaling approach as a reliable framework for reactor scale-up. The findings provide an experimental basis for future industrial implementation of jet loop reactors in chemical process engineering.