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The objective of this work is to investigate adsorption separation of liquid‐phase xylene isomers using ultramicroporous carbon spheres. The synthesized glucose‐based adsorbent (UMC‐xyl) enabled the challenging separation of liquid‐phase p‐xylene/m‐xylene with an adsorption selectivity of 53 as well as p‐xylene uptake of 91mg/g, outperforming a series of commercial adsorbents including the industrial benchmark KBaX. The micropore diffusion model was used to give the best fit to the adsorption kinetics of UMC‐xyl with a rate achieved higher than KBaX. The xylene isomer separation was facilitated by the narrow ultramicropore size distributed at 5.8–6.8 Å in UMC‐xyl via a synergistic kinetic and size‐sieving separation mechanism. Breakthrough experiments confirmed the effectiveness of UMC‐xyl in the dynamic selective separation of p‐xylene from xylene isomers, together with superior multiple‐cycle eluent regenerability under the synergistic effects of the "like‐dissolve‐like" principle and π–π interaction. The work opens a new direction of using porous carbon adsorbents for continuous liquid‐phase separation of challenging hydrocarbon isomers. [ABSTRACT FROM AUTHOR]

• Ideal molecular sieving of C 3 H 6 /C 3 H 8 with superior C 3 H 6 uptake of 2.37 mmol/g. • C 3 H 6 is admitted to the pore even at LTA apertures of < 4 Å when exchanged Ag+. • Exchanged Ag+ increases adsorption kinetics of C 3 H 6 by an order of magnitude. • Hydrophobic modification significantly suppresses the competition from water vapor. Separating C 3 H 6 /C 3 H 8 is a challenging task owing to their similar sizes and boiling points. In this study, we report a sequential and partial Ag+/Ca2+ ion-exchanged zeolite that exhibits ideal C 3 H 6 /C 3 H 8 molecular sieving. Moreover, the zeolite exhibited superior C 3 H 6 uptake of 2.37 mmol/g and molecular packing density (∼77% packing of liquid C 3 H 6) at an extremely high C 3 H 6 : Ag+ ratio of 21.5 with Ag content as low as 1.18 wt%. The (Ag+, Ca2+) cations were sequentially exchanged into LTAs by comprehensively considering the extra-framework cation distribution and site preferences for different cations. By exchanging Ag+ with Na+ in the extra-framework of LTA, C 3 H 6 can be admitted even at the average LTA apertures of sizes < 4 Å. Meanwhile, exchanged Ag+ also increased the adsorption kinetics of C 3 H 6 by an order of magnitude. Hydrophobic modification on Ca-Ag-LTA was successfully achieved to significantly suppress the competition from water while retaining excellent regenerability in multiple cycles. The strategy of binary ion exchange to delicately tune the pore channels and chemistry and selectively admit molecules with beneficial kinetics might potentially be broadened to other industrial separation processes. [ABSTRACT FROM AUTHOR]

• High-performance adsorbents with diamine-functionalized mesoporous support (P/D-SD) effectively remove trace CO 2 from C 2 H 2. • P/D-SD shows high CO 2 adsorption capacity (1.76 mmol/g at 298 K and 0.0004 bar) and CO 2 /C 2 H 2 IAST selectivity surpassing 105. • P/D-SD produces highly pure C 2 H 2 (>99.9 %) from CO 2 /C 2 H 2 mixtures, with adsorption performance unaffected by moisture. • P/D-SD shows fast CO 2 adsorption kinetics and excellent cycling stability. The removal of trace carbon dioxide (CO 2) from acetylene (C 2 H 2) through adsorption poses a significant challenge due to their similar kinetic diameters and physical properties. Here, we report a novel solid amine adsorbent, polyethyleneimine-diethanolamine functionalized silica dioxide (termed P/D-SD), which exhibited a remarkable CO 2 adsorption capacity of 1.76 mmol/g at 298 K and 0.0004 bar. The IAST selectivity of the CO 2 /C 2 H 2 (1/99, v/v) mixture of P/D-SD was 7.98E + 05. The exceptional separation performance of P/D-SD is demonstrated through breakthrough experiments, producing ultra-high purity C 2 H 2 (greater than 99.9 %) from CO 2 /C 2 H 2 (1/99) mixtures. Its CO 2 adsorption performance remains largely unaffected under different humidity condition. Furthermore, P/D-SD exhibited excellent stability in the adsorption–desorption cycle and rapid CO 2 adsorption kinetics at different temperatures when compared with P-SD. The adsorption mechanism of P/D-SD with CO 2 was studied as a chemisorption process via in situ DRIFTS. [ABSTRACT FROM AUTHOR]

[Display omitted] • The ABC packing clover-like topology equipped TzDABA COF with evenly divided pores. • Charge-induced adsorption of cationic dyes was promoted on carboxyl-modified COF. • High adsorption capacities of MB, CV and MG were 315, 533 and 1168 mg g−1. • Size dependent adsorption of cationic dyes was realized via clover-like topology. Covalent organic frameworks (COFs) with designable structure and well-defined aperture are highly desired as novel adsorbents for elimination of dye pollution. Herein, a new carboxyl-functionalized covalent organic framework (TzDABA COF) with clover-like topology was synthesized by the condensation of 1,3,5-tris(4-formyl-phenyl) triazine (Tz) and 3,5-diaminobenzoic acid (DABA) under solvothermal conditions. The obtained TzDABA COF exhibited rapid adsorption kinetics and excellent adsorption capacities toward multiple cationic organic dyes including methylene blue (MB, 315 mg g−1), crystal violet (CV, 533 mg g−1) and malachite green (MG, 1168 mg g−1) owing to the formation of strong electrostatic interaction and π-π interaction between COF framework and organic dye molecules. Remarkably, with particular ABC stacking mode and an abundant of carboxyl functional groups integrated in the clover-like architecture, the anionic TzDABA COF could effectively separate organic dyes in different modes, representing the first case of carboxyl-functionalized clover-like COF for dye separation based on charge effect and size effect. This study paves a new pathway toward construction of carboxyl-functionalized clover-like COFs and reveals their desiring prospect in field of dyes separation and purification. [ABSTRACT FROM AUTHOR]