A novel condensation reactor for efficient CO2 to methanol conversion for storage of renewable electric energy

Abstract

A novel reactor design for the conversion of CO 2 and H 2 to methanol is developed. The conversion limitations because of thermodynamic equilibrium are bypassed via in situ condensation of a water/methanol mixture. Two temperatures zones inside the reactor ensure optimal catalyst activity (high temperature) and full conversion by condensation at a lower temperature in a separate zone. Due to this full gas conversion there is no need for an external recycle of reactants. Experimental work confirmed full carbon conversion (>99.5%) and high methanol selectivity (>99.5% on carbon basis). Additionally, it was shown that due the temperature gradient inside the reactor significant reaction rates are achieved under natural convection conditions.

Investigation of the Phase Equilibria of CO2/CH3OH/H2O and CO2/CH3OH/H2O/H2 Mixtures

“…The principle of removing the products through condensation was also demonstrated by Bos and Brilmann, while here no condensation under reaction conditions was applied, but a reactor with two temperature zones [14]. Proof that an in situ condensation can take place was given by van Bennekom et al with a view cell operating in a semi-batch mode [16].…”

“…The current research on the CH 3 OH synthesis covers a broad pressure range. The pressure varies from atmospheric pressure processes with the aid of a plasma [8], over mid-pressure (30-50 bar) processes [9][10][11][12][13][14] to high-pressure processes [15][16][17][18][19][20][21]. Mostly, heterogeneous catalysts based on copper, gold, or palladium are applied.…”

A Review of The Methanol Economy: The Fuel Cell Route

“…Additionally, the tube-cooled reactor is also an option for this process [51]. Other novel reactors focusing on the in situ condensation and removal of the produced water and methanol, e.g., by using membrane reactors [39,52], sorption-enhanced [53,54] and natural convection [55] processes, are also reported at research level. However, hydrogenation of CO 2 to methanol by reaction 2 introduces more water, which has a detrimental effect on the conventional Cu-based catalyst [56].…”

Renewable Methanol Synthesis

“…In situ condensation of reaction products (methanol and water) enables the equilibrium reactions to proceed to near completion [165][166][167]. Considering that the highest cost for renewable methanol production reports to the electrolytic recovery of hydrogen, methanol product condensation offers a means to recover reactant recycling costs.…”

“…On a laboratory scale it was possible to produce methanol to full efficiency in one pass in a condensation reactor by distilling the products in situ [163,166]. Whether this process is scalable does not seem to have been investigated up to now.…”