Abstract

Heterogeneous Catalytic Hydrogenations in Flow

Viktor Gyollai, Senior Flow Chemist, AM Technology

Continuous hydrogenation has inherent cost, performance and safety advantages. These stem from the use of smaller equipment and reduced inventory of gas under pressure. This concept is not new and continuous packed bed systems have been used for many decades in some industries. Flow hydrogenation where catalyst particles flow with the process material offers significant advantages, however, in terms of temperature control and greater catalyst choice. Proof of principle of such methods can be demonstrated by flowing gas, process fluid and catalyst particles through a reactor. Although the method works well over short cycle times, accumulation and blockage is inevitable at some point. Sustained continuous hydrogenation requires a flow pattern where liquid and catalyst flow down through the reactor and hydrogen flows up. This ensures uniform distribution of gas, liquids and solids and can operate for days or weeks without interruption. It also presents formidable technical challenges relating to pumps, gas disengagement, flow control and pumping. These problems however are solvable using novel hardware solutions and this presentation covers development work and lab studies which have been in progress for over 5 years.