Neue Konvertersysteme für die Methanol‐Synthese

Abstract

Um bei Gleichgewichtsreaktionen groBe Energieeinsparungen zu erreichen, mu13 man nicht nur bessere Katalysatoren entwickeln, sondern auch Verfahren mit einem hoheren Umsatz im Reaktor, wenn moglich so hoch, daB auf eine Rezirkulation der Restgasen verzichtet werden kann. Zu diesem Zweck sind zwei neue Verfahren fur die Methanol-Herstellung entwickelt worden; uber das zweite wird zum ersten Ma1 berichtet. Die zwei neuen Reaktorkonzepte basieren auf dem New converter systems for methanol synthesis. Farreaching energy savings in equilibrium reactions requires development not only of better catalysts but also processes with higher conversions in the reactor; wherever possible, so high that recirculation of residual gases is unnecessary. With this aim in mind, two new processes have been developed for methanol production and this paper represents the first report about the second of these processes. The two new reactor concepts are based on the gas/solid/solid-trickling film reactor GSSTFR and the reactor with intermediate product removal RSIPR. In the case of the GSSTFR, the product formed at the catalyst is removed directly from the reactor with a solid adsorbent which moves down through the catalyst bed. Conversions of 100% are achieved in the simplest wayrecirculation becomes unnecessary. Savings in investment costs, energy, and raw materials are discussed and compared with the Lurgi process. With the RISPR, high conversions are achieved by selective absorption of the methanol at the temperature of reaction. Tetraethylene glycoldimethylether, TEGDME, is selected as solvent for this purpose. A possible flow scheme is also shown for this process and savings are estimated. Possible savings are so promising that further development on a semi-industrial scale is recommended. Einfuhrung

Methanol Synthesis

“…High-boiling tetraethylene glycol dimethyl ether (TEGDME) serves this purpose [386,387]. High-boiling tetraethylene glycol dimethyl ether (TEGDME) serves this purpose [386,387].…”

A theoretical analysis of methanol synthesis from CO2 and H2 in a ceramic membrane reactor

“…For example, an attempt at in situ product removal was made by Westerterp et al [8] who proposed the selective adsorption of water and methanol on a solid, in a trickle bed reactor. On the other hand, water produced during methanol synthesis via CO 2 hydrogenation (reaction (2)) greatly reduces the methanol synthesis rate by suppressing reaction (3).…”

Methanol production by bi‐reforming

“…However, in 1923 the first catalyst has been developed for large scale methanol production . The process operated at a high pressure (30 MPa) and high temperatures (573–673 K) over a Zn/Cr 2 O 3 catalyst, which was replaced in 1966 by a much more efficient Cu/Zn/Al 2 O 3 catalyst allowing operation under much milder conditions, as mentioned in the section “Difficulties and Challenges” . Nowadays, methanol can also be synthesized from a nonstoichiometric mixture of hydrogen, carbon dioxide and carbon monoxide (90:5:5) at 5–10 MPa and 500–550 K over the previously mentioned Cu/ZnO/Al 2 O 3 type of catalyst .…”