Page 173 - CW E-Magazine (11-2-2025)

Special Report

High pressure molecular intensification in view of the need products were bicarbonates, unstable
sieving of high-humidity for CO removal with lower energy carbamates, etc. Their system consists of
2
C H /C H mixture by a consumption for recovery.] tertiary amine diethanolamine (DEEA) as
2
2
4
6
hydrophobic flexible MOF Computational study on CO the main regent with several monoamines
[This column has covered some papers absorption mechanism and 2 as promoters. DEEA was combined with
on adsorption-based separations for structure-activity relationship piperazine (PZ) and 4-amino-1-methyl-
C H /C H and C H /C H in view of in biphasic solvent piperidine (PP) and gave a loading of
3
4
2
8
3
2
6
6
high capital and energy costs associated 0.988 mole CO per mole amine. Regene-
2
with cryogenic distillation. Adsorbents F. Tang et al have referred to primary ration duty was low at 2.14-GJ/t. (Chem.
st
have been developed to even reverse the amino groups showing stronger proton Eng. Jl., 2024, 493, 1 August, 152699;
selectivity for alkane vs alkenes.] affinity than secondary ones, when poly- DOI:10.1016/j.cej.2024, 152699).
amines follow zwitterion mechanism. Mass transport mechanism of
Y-W. Zhang et al have reported a It is stressed that the biphasic solvents
flexible adsorbent showing molecular are expected to improve the efficiency nitrate selective nanofiltration
sieving at ambient temperature and high of CO capture and reduce the energy (NF) membrane on the basis
pressure, even under high humidity. A consumption in desorption of CO of the Donnan stearic pore
2
high transition pressure of 16.6 atm, is from loaded solutions. DFT calculation model with dielectric exclusion
2
found for C H at 25°C, and even more were adopted. Selection of diamines (DSPH-DE)
2
4
importantly C H is completely excluded is referred: 1,4 butanediamine (BDA)
6
2
below the pore-opening pressure of 10 and N-(2-aminoethyl)ethanolamine N. Cevallos-Cueva et al have worked
atm. (Angew. Chem. Intl. Ed.,2024; DOI: (AEEA) with typical phase separation on the troublesome problem of nitrate
10.1002/anie.202317648). promoters – 2-(diethylamino)ethano- removal, whose discharge into waste
streams is not allowed. The title stra-
Magnetic nanoparticles lamine (DEEA), and N,N,N’,N’’-penta- tegy has succeeded in nitrate/sulphate
(MNPs)-induced sorbent methyldiethylenetriamine (PMDETA) separation. Thin film composite mem-
regeneration for Direct Air were selected. (Chem. Eng. Jl., 2024, branes were made having a polyamide
Capture (DAC) 493, 1 August, 152653; DOI:10.1016/ selective layer. This required inter-
j.cej.2024.152653).
[This column has covered many papers on facial polymerisation of piperazine and
removal of CO , including that from air, Novel tri-solvent amines trimesoyl chloride. (Chem. Eng. Jl., 2024,
2
which is attracting some attention.] 493, 1 August, 152775; DOI:10.1016/j.
absorption for flue gas CO cej.2024.152775).
2
Direct capture of CO from air involves capture: Efficient absorption
2
considerable energy consumption. K. and regeneration with low 1,3-Dioxalane (DO)
Li et al have reported an effective and energy consumption production via reactive
scalable adsorbent sorbent regeneration distillation (RD) combined
method for liquid DAC solvents based G. Li et al have synthesised a novel with vapour permeation (VP)
on MNPs heating with AC magnetic tri-solvent amine absorbent. This system
fields. MNPs can be directly heated to gave high CO loading with cyclic S. Liu et al have reported the title process
2
provide uniform and rapid volumetric capacity. The regeneration heat duty was to give 99.9 wt% DO in a new energy-
heating. Aqueous solution of K-Sar- reduced to 2.14-GJ/tCO . The reaction saving and cost-reduction process.
2
cosinate was used to demonstrate the
above method. MNPs can be used for
several recycles. (AIChE Jl, 2024; DOI:
10.1002/aic.18500).
Absorption of CO ;
2
Desorption of loaded amine
solution
[This column has covered several papers
on this subject and this area continues
to attract a lot of attention for further
Chemical Weekly February 11, 2025 173

Contents Index to Advertisers Index to Products Advertised