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LICENSORS

Haldor-Topsøe JM/Davy Lurgi/AirLiquide Toyo Engineering
Syngas generation
Catalyst Own Own Sud-Chemie Own (ISOP)
SMR or ATR or SMR SMR or ATR or SMR or
Reactor
+ ATR GHR + ATR SMR + ATR SMR + ATR
Methanol converter

Catalyst Own Own Sud-Chemie MGC
Adiabatic and BWR BWR and gas cooled BWR and gas cooled in
Reactor MFR-Z ®
in series combination series

TABLE 5 - Main Methanol Licensors and Technologies

Commonly employed catalysts contain copper, zinc ox- for transforming carbon dioxide containing gases into a
ide and alumina that are also able to reduce the forma- synthesis gas suitable for methanol production.
tion of by-products (e.g. dimethyl ether, higher alcohols, (Source: ‘Renewable Methanol Report’ from Methanol
carbonyl compounds and methane). Institute)
Different types of industrial reactors, both adiabatic
and isothermal, have been developed and applied to The pathway involving a RWGS step for converting car-
achieve an optimal temperature profile in the convert- bon dioxide into synthesis gas and then into methanol,
er; quench reactors, steam raising reactors (BWR), was examined, either theoretically and experimentally
gas cooled reactors and adiabatic reactors are the till the pilot scale level, in the 1999-2019 period 28,29,30,31 .
most commonly used. Briefly, it is mentioned that con- However, this approach would have provided a viable
verters differ from the way reaction heat is removed. solution for utilising carbon dioxide only if the RWGS
Quench reactors employ cold-shot injection of syngas could occur at high temperature – high pressure con-
within or between the reaction beds while adiabatic ditions (HT-HP; T > 750°C and P > 5 MPa) for shifting
converters use intercooling between beds. Steam its equilibrium towards the carbon monoxide and water
raising reactors are isothermal shell and tube reactors, production and for avoiding or reducing the contribution
temperature control is achieved by carefully selecting of the parasitic methanation reactions [6] and [7].
the pressure of the boiler feed water circulating on the CO + 4 H → CH + 2H O (ΔH° = - 164 kJ/mol) [6]
4
2
2
2
shell side leading to steam generation. Gas-cooled CO + 3 H → CH + H O (ΔH = - 206 kJ/mol) [7]
4
2
2
converters use the cold feed gas as cooling medium
on the tube side of a shell and tube converter while Noteworthy, the studies devoted to this kind of process
heated feed gas passes through the catalyst-filled solution, that was referred to as CAMERE process could
shell side. Variations of the four types of convert- not show any advantage with respect to the via syngas
ers are currently employed by the major commercial processes currently utilised because the development of
methanol licensors and among them we mention; a HT-HP RWGS stage would have required the utilization
Haldor-Topsøe AS, Johnson Matthey Catalyst (JM) of a furnace that compromises the possibility of devel-
& Davy Process Technology (DPT), Lurgi-AirLiquide, oping a carbon-dioxide-consuming methanol production
Toyo Engineering. These licensors also provide highly process.
integrated syngas production systems. Now we have instead noted that a HT-HP electrified re-
The following table 5 summarizes the mayor licensors actor (E-RWGS) could overcome the disadvantages of
together with their preferred technologies for catalysts the CAMERE process and accordingly we completed a
and reactors study describing the performances of such a solution.
The block scheme of the process is described in Figure
Carbon dioxide utilisation 2 and includes the three main unit operations of hydro-
gen production with water electrolysis, the syngas pro-
with Electrified Reverse Water duction with E-RWGS and the methanol synthesis.
Gas Shift (E-RWGS) More in detail, we report that the envisaged solution
in methanol synthesis could be applied to several carbon dioxide rich steams
and particularly the utilisation of bio-gas streams. In
By assuming a Carbon Capture and Utilization (CCU) this case, the process would allow a bio-methane and
perspective, this paragraph examines a process solution methanol production entirely achievable from renewable
currently under development in the Rosetti Marino S.p.A. sources.
framework , in which the chemical transformation of It is briefly mentioned that electrified reactors can be
27
carbon dioxide into methanol is obtained by combining designed with resistance heated catalysts exploiting the
unit operations of water electrolysis, Electrified Reverse Joule effect aiming at: i) increasing the heat transfer ef-
32
Water Gas Shift (E-RWGS) and Methanol synthesis reac- ficiency required by the strongly endothermic reactions,
tors. More in detail, this document describes a process ii) reducing the radial temperature gradients through the

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