11 Toward Industrialization of Ionic Liquids
269
gas for fueling stations and is one of the guiding examples for disruptive innovations
based on the unique properties of ionic liquids. The combined properties of sparingly soluble compressed gases with very low compressibility, high thermal stability,
and negligible vapor pressures of ionic liquids were key phenomena to realize this
technology.
Another extraordinary industrial application of ionic liquids is their use in cooling
high-temperature metallurgical devices, a technology developed jointly by proionic
and Mettop and commercialized by Mettop as ILTEC Technology in 2014. Working
together with the SMS Group, a world leader in metallurgical plant construction
and mechanical engineering, the ILTEC process has been running successfully since
2016 at several industrial sites. Special ionic liquids are used as coolants and have
negligible reactivity with molten metals and slags. The ionic liquids are far superior to the previous state-of-the-art cooling medium for metallurgical devices, water,
which can cause catastrophic explosions if the cooling device becomes compromised. By developing these ionic liquid cooling media, it is now possible to redesign
metallurgical aggregates (e.g., furnaces, lances, tap holes, or off-gas systems) and
cross the heretofore forbidden line of cooling underneath the bath level of metal
melts. It is also possible to retrofit ionic liquid cooling media into existing plants.
In addition to their inherent safety, these ionic liquids operate at much higher temperatures as compared to water, making it possible to recover energy, for example,
by Rankine cycle processes. With knowledge gathered during the development of
high-temperature metallurgical cooling applications, proionic currently operates a
pilot project of non-flammable hydraulic systems for the use in high-temperature
environments.
Another major field is the utilization of ionic liquids as solvents; no less than
15 implemented applications can be found in Table 11.1. Arkema commercialized
a process for the liquid fluorination of saturated or unsaturated compounds bearing
C–Cl groups via a catalyzed reaction with hydrogen fluoride in certain ionic liquids.
The water-gas shift reaction is active at the pilot stage at Clariant. By the use of a
SILP catalyst (supported ionic liquid phase [36]), the reaction can be performed at
“ultra-low” temperatures [37, 38], and trace amounts of carbon monoxide can be
removed from the water gas. Another SILP-based application with superior performance is operated at Evonik at the pilot scale. The process uses ionic liquids for
the hydroformylation of C3/C4 feedstock to yield the corresponding aldehydes [39].
Other chemical reactions with ionic liquids include the commercial synthesis of inorganic materials with defined particle size and a pilot-scale reaction for the synthesis
of alcohols, both performed by IoLiTec.
The outstanding solvation properties of ionic liquids are used in the so-called
HiPerPol process for the recovery of high-value polymers from waste. This recycling
process is underway at the pilot scale at C-Tech Innovation and uses post-industrial
composite packaging waste as feedstock; for example, the separation of heavy metal
additives from recovered PVC produces high-quality polymer powders [40].
A remarkable property of highly coordinating ionic liquids (e.g., 1,3dialkylimidazolium acetates, chlorides, or dialkylphosphates) is their ability to dissolve biomass by hydrogen-bond donor–acceptor interactions. Dissolution occurs
269
gas for fueling stations and is one of the guiding examples for disruptive innovations
based on the unique properties of ionic liquids. The combined properties of sparingly soluble compressed gases with very low compressibility, high thermal stability,
and negligible vapor pressures of ionic liquids were key phenomena to realize this
technology.
Another extraordinary industrial application of ionic liquids is their use in cooling
high-temperature metallurgical devices, a technology developed jointly by proionic
and Mettop and commercialized by Mettop as ILTEC Technology in 2014. Working
together with the SMS Group, a world leader in metallurgical plant construction
and mechanical engineering, the ILTEC process has been running successfully since
2016 at several industrial sites. Special ionic liquids are used as coolants and have
negligible reactivity with molten metals and slags. The ionic liquids are far superior to the previous state-of-the-art cooling medium for metallurgical devices, water,
which can cause catastrophic explosions if the cooling device becomes compromised. By developing these ionic liquid cooling media, it is now possible to redesign
metallurgical aggregates (e.g., furnaces, lances, tap holes, or off-gas systems) and
cross the heretofore forbidden line of cooling underneath the bath level of metal
melts. It is also possible to retrofit ionic liquid cooling media into existing plants.
In addition to their inherent safety, these ionic liquids operate at much higher temperatures as compared to water, making it possible to recover energy, for example,
by Rankine cycle processes. With knowledge gathered during the development of
high-temperature metallurgical cooling applications, proionic currently operates a
pilot project of non-flammable hydraulic systems for the use in high-temperature
environments.
Another major field is the utilization of ionic liquids as solvents; no less than
15 implemented applications can be found in Table 11.1. Arkema commercialized
a process for the liquid fluorination of saturated or unsaturated compounds bearing
C–Cl groups via a catalyzed reaction with hydrogen fluoride in certain ionic liquids.
The water-gas shift reaction is active at the pilot stage at Clariant. By the use of a
SILP catalyst (supported ionic liquid phase [36]), the reaction can be performed at
“ultra-low” temperatures [37, 38], and trace amounts of carbon monoxide can be
removed from the water gas. Another SILP-based application with superior performance is operated at Evonik at the pilot scale. The process uses ionic liquids for
the hydroformylation of C3/C4 feedstock to yield the corresponding aldehydes [39].
Other chemical reactions with ionic liquids include the commercial synthesis of inorganic materials with defined particle size and a pilot-scale reaction for the synthesis
of alcohols, both performed by IoLiTec.
The outstanding solvation properties of ionic liquids are used in the so-called
HiPerPol process for the recovery of high-value polymers from waste. This recycling
process is underway at the pilot scale at C-Tech Innovation and uses post-industrial
composite packaging waste as feedstock; for example, the separation of heavy metal
additives from recovered PVC produces high-quality polymer powders [40].
A remarkable property of highly coordinating ionic liquids (e.g., 1,3dialkylimidazolium acetates, chlorides, or dialkylphosphates) is their ability to dissolve biomass by hydrogen-bond donor–acceptor interactions. Dissolution occurs