Dehydrogenation of methanol to formaldehyde using sodium-based catalysts on a mini-plant scale

Formaldehyde, an important chemical precursor in many industrial processes, is produced by various methods, each with their own efficiency and challenges. The presented thesis provides an in-depth investigation of the gas-phase dehydrogenation of methanol to formaldehyde, focusing on the potential of sodium compounds, particularly sodium and sodium carbonate, as catalysts. Furthermore, it presents the state of the art in formaldehyde production, highlighting the need for innovative approaches to meet growing industrial demands and increased environmental concerns. A specially designed and constructed experimental setup, the MEDENA mini-plant, is at the center of this thesis, allowing reaction tests to be carried out and providing important insights into the behavior of substrates, products, and catalysts. Sodium metal and sodium carbonate were studied as catalysts for the direct dehydrogenation of methanol to formaldehyde. Additionally, particular attention was given to the evaluation of the sodium dosing system. The results indicated that sodium vapor can be dosed continuously while at the same time, obtaining high formaldehyde and hydrogen yields. ... mehrMoreover, a novel heating method for the dehydrogenation of methanol to formaldehyde was examined. Unlike traditional heating techniques, which often employ indirect or convective heat transfer, direct resistance heating applies electrical current through the catalyst body. This direct approach ensures rapid and uniform heating, minimizing potential heat losses and ensuring the most favorable reaction conditions. Due to its efficiency, the direct resistance heating concept has the potential to transform conventional methods of formaldehyde production, offering both economic and environmental benefits. In summary, this research aimed to improve formaldehyde production techniques by bridging the gap between conventional routes and newly developed approaches. This work paves the way for environmentally friendly, efficient and sustainable formaldehyde production, thereby preparing the ground for future industrial applications.