5 Commercial Aspects of Biomass Deconstruction with Ionic Liquids
89
liquid instead of the conventional amine process provided key advantages due to
the nucleophilic catalytic activity of 1-alkylimidazole that increased the space-time
yield (STY) by a factor of 86,000 as well as the economic reclamation of the 1alkylimidazole by IL deprotonation [20, 21]. Such a remarkable improvement in
process performance was crucial to accelerate the industrial deployment of new solvents, such as ILs. Likewise, the application of an IL-based pretreatment process
will have to feature exclusive selling points and key processing advantages for it
to compete with processes of similar or higher technology readiness level. From a
high-level perspective, the key advantages of IL-based pretreatment compared to
peer technologies include: (1) low operating pressure and reduced solvent losses
as ILs are non-volatile solvents, (2) potentially lower capital cost of a pretreatment
reactor compared to aqueous or organic solvent due to ILs’ non-volatile nature, [22]
(3) lower enzymes loading and smaller operation units due to lignin pre-extraction
during pretreatment, [23] (4) production of high-quality lignin of high valorization
potential, [24] and (5) robust process performance that is highly independent of
feedstock type and composition [25–28].
Despite these appealing advantages, the very high cost of ILs compared to aqueous
or organic solvents has been always highlighted as the key barrier for their large-scale
application [29].
However, it was only recently demonstrated that the high cost associated with
ILs is not inherent, but it is a consequence of choosing historically dominant ILs
(dialkylimidazolium cations with poly-fluorinated anions) [30]. Overcoming the IL
cost barrier was the key turning point that enabled the discussion of ionoSolv’s
potential commercialization.
5.1.1 Technology Readiness Level
The path of translating academic research to a large-scale industrial process follows
several validation and development steps. Technology readiness level (TRL) is a
popular concept adapted in several sectors (e.g., space, defence, and oil and gas
operations) to measure technology maturity level and its readiness for large-scale
deployment. The scale and definition are slightly different to suit the requirement of
the different sectors; however, they all have the same general structure and pathway
starting from proof of concept and lab experiments to pilot testing and demonstration
and eventually to a mature industrially proven technology. Figure 5.1 shows the TRL
scale and definition according to the 2017 European Commission, which can be used
for renewable energy technologies [31]. In the context of this chapter, TRLs from
1 to 7 were used to describe the development pathway of using ILs for biomass
pretreatment with special focus on our own experience in the development of the
ionoSolv process.
89
liquid instead of the conventional amine process provided key advantages due to
the nucleophilic catalytic activity of 1-alkylimidazole that increased the space-time
yield (STY) by a factor of 86,000 as well as the economic reclamation of the 1alkylimidazole by IL deprotonation [20, 21]. Such a remarkable improvement in
process performance was crucial to accelerate the industrial deployment of new solvents, such as ILs. Likewise, the application of an IL-based pretreatment process
will have to feature exclusive selling points and key processing advantages for it
to compete with processes of similar or higher technology readiness level. From a
high-level perspective, the key advantages of IL-based pretreatment compared to
peer technologies include: (1) low operating pressure and reduced solvent losses
as ILs are non-volatile solvents, (2) potentially lower capital cost of a pretreatment
reactor compared to aqueous or organic solvent due to ILs’ non-volatile nature, [22]
(3) lower enzymes loading and smaller operation units due to lignin pre-extraction
during pretreatment, [23] (4) production of high-quality lignin of high valorization
potential, [24] and (5) robust process performance that is highly independent of
feedstock type and composition [25–28].
Despite these appealing advantages, the very high cost of ILs compared to aqueous
or organic solvents has been always highlighted as the key barrier for their large-scale
application [29].
However, it was only recently demonstrated that the high cost associated with
ILs is not inherent, but it is a consequence of choosing historically dominant ILs
(dialkylimidazolium cations with poly-fluorinated anions) [30]. Overcoming the IL
cost barrier was the key turning point that enabled the discussion of ionoSolv’s
potential commercialization.
5.1.1 Technology Readiness Level
The path of translating academic research to a large-scale industrial process follows
several validation and development steps. Technology readiness level (TRL) is a
popular concept adapted in several sectors (e.g., space, defence, and oil and gas
operations) to measure technology maturity level and its readiness for large-scale
deployment. The scale and definition are slightly different to suit the requirement of
the different sectors; however, they all have the same general structure and pathway
starting from proof of concept and lab experiments to pilot testing and demonstration
and eventually to a mature industrially proven technology. Figure 5.1 shows the TRL
scale and definition according to the 2017 European Commission, which can be used
for renewable energy technologies [31]. In the context of this chapter, TRLs from
1 to 7 were used to describe the development pathway of using ILs for biomass
pretreatment with special focus on our own experience in the development of the
ionoSolv process.