1-Ethyl-3-methylimidazolium bis[(trifluoromethyl)sulfonyl]imide
([EMIM][Tf2N]) ionic liquid as a novel absorbent has excellent
performance in BTX absorption. However, compared with the traditional
method using triethylene glycol (TEG), the sustainability of the former
is unknown. Thus, to bridge the gap and give a comprehensive evaluation
of its industrialization potential, a methodology-integrated energetic,
economic, and environmental assessment was employed. The assessment
results show that the heating and cooling energy consumptions of the
TEG process are 1.08 and 0.74 times higher than those of the [EMIM][Tf2N] process, respectively. But through heat integration, 5%
hot and 3.4% cold utilities can be saved for the [EMIM][Tf2N] process. In terms of economic performance, the total annual costs
for TEG and [EMIM][Tf2N] processes are 0.6111 and 0.4841
M$/year, respectively, and the latter is 26.3% lower than the former.
As for the environmental assessment, the results indicated that compared
with the TEG scenario, the [EMIM][Tf2N] scenario without
absorbent recovery presented higher environmental burdens in all categories,
and the largest difference lies in acidification, for which the latter
is 42 times that of the former. However, when considering the absorbent
recovery, the results are contradictory. Thus, the comprehensive assessment
methodology proved that the [EMIM][Tf2N]-based BTX absorption
process is sustainable and can be a potential industrialization technology.