In Scheme 9.2 a representation of Value-Chains based on CO 2 –CH 3 OH is
shown which gives a cumulative idea of the products that can be obtained from CO 2
using CH 3 OH as intermediate.
The integrated approach can potentially convert over 1 Gt CO2 /y.
9.2.5.2 Dimethyl Ether, CH 3 OCH 3 , DME
DME is a low boiling liquid, used as an intermediate in the synthesis of
methyl acetate, dimethyl acetate and light olefins or as a fuel for substituting
diesel (40+% better cetane number). It is produced at a rate of ca. 6 Mt/y
(2018). Most of it is produced in China.
DME is produced [39] upon methanol dehydration, (Eq. 9.16a) but the
one-reactor technology based on CO 2 hydrogenation is very attractive (Eq. 9.16b)
as reduces both CAPEX and OPEX [40].
2CH 3 OH ! CH 3 OCH 3 þ H 2 O
ð9:16aÞ
2CO 2 þ 6H 2 ! CH 3 OCH 3 þ 3H 2 O DH
298K ¼ À122:2 kJ mol
À1
ð9:16bÞ
In practice, the catalyst for CO 2 hydrogenation to methanol is coupled with the
dehydration catalyst so to run both processes in a single reactor.
Scheme 9.2 A summary of CH 3 OH-centered Value-Chains for CO 2 utilization. (tc = thermal
catalysis; ec = electro catalysis. Figures in parentheses give the actual market of products made
using fossil-C: in future they could be made from CO 2 ). Reprinted/adapted by permission from
Ref. [6b], Copyright 2019
160
9 Circular Economy and Carbon Dioxide Conversion
shown which gives a cumulative idea of the products that can be obtained from CO 2
using CH 3 OH as intermediate.
The integrated approach can potentially convert over 1 Gt CO2 /y.
9.2.5.2 Dimethyl Ether, CH 3 OCH 3 , DME
DME is a low boiling liquid, used as an intermediate in the synthesis of
methyl acetate, dimethyl acetate and light olefins or as a fuel for substituting
diesel (40+% better cetane number). It is produced at a rate of ca. 6 Mt/y
(2018). Most of it is produced in China.
DME is produced [39] upon methanol dehydration, (Eq. 9.16a) but the
one-reactor technology based on CO 2 hydrogenation is very attractive (Eq. 9.16b)
as reduces both CAPEX and OPEX [40].
2CH 3 OH ! CH 3 OCH 3 þ H 2 O
ð9:16aÞ
2CO 2 þ 6H 2 ! CH 3 OCH 3 þ 3H 2 O DH
298K ¼ À122:2 kJ mol
À1
ð9:16bÞ
In practice, the catalyst for CO 2 hydrogenation to methanol is coupled with the
dehydration catalyst so to run both processes in a single reactor.
Scheme 9.2 A summary of CH 3 OH-centered Value-Chains for CO 2 utilization. (tc = thermal
catalysis; ec = electro catalysis. Figures in parentheses give the actual market of products made
using fossil-C: in future they could be made from CO 2 ). Reprinted/adapted by permission from
Ref. [6b], Copyright 2019
160
9 Circular Economy and Carbon Dioxide Conversion