To screen suitable low transition
temperature mixtures (LTTMs)
as solvents for the extraction process of a benzene and cyclohexane
mixture, the extraction performance of the LTTMs (25 hydrogen-bond
donors (HBDs) and 13 hydrogen-bond acceptors (HBAs)) was assessed
based on COSMO-SAC predictions of infinite dilution activity coefficients
of benzene and cyclohexane in different LTTMs. The effects of the
molar ratio of HBD to HBA on extraction efficiency were also observed
in the meantime. It is found that the LTTM sulfolane-tetrabutylammonium
bromide 5:1 (ST 5:1), which has excellent extraction performance,
is the most promising solvent. To explain the difference of extraction
efficiency of various LTTMs, σ-profiles were adopted to study
the molecular interactions between LTTMs and benzene or cyclohexane.
The analysis for geometry, interaction energy, independent gradient
model (IGM) and atoms in molecules (AIM) was performed to explain
interaction mechanisms between benzene/cyclohexane and HBD/HBA. Moreover,
the liquid–liquid equilibrium (LLE) data of benzene–cyclohexane-ST
5:1 were experimentally measured, and the consistency tests were conducted
using the Othmer–Tobias equation. In addition, the LLE data
were employed to fit the binary interaction parameters of the NRTL
activity coefficient model. In conclusion, the LTTM ST 5:1 shows good
extraction performance, which provides a reference for the extractive
separation of the benzene–cyclohexane mixture in industry.
Reactive
dividing wall column (RDWC) is a highly integrated configuration
where reaction and separation take place in a single equipment simultaneously.
In this study, three self-heat recuperative reactive dividing wall
column processes are developed to reduce the energy consumption of
RDWC. Latent heat and sensible heat in the processes are recovered
by self-heat recuperation technology. The heat exchanger network using
pinch analysis is applied to optimize the energy utilization. Total
energy consumption, total annual cost, CO2 emissions, and
thermodynamic efficiency are evaluated. Compared with the RDWC, the
results demonstrate that the optimal design of the self-heat recuperative
processes reduces the energy consumption by 58.1% and decreases the
total annual cost by 17.8%. Apart from that, the CO2 emissions
of the optimal design are 87.9% lower than the RDWC and the thermodynamic
efficiency can be increased to 31.4%.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.