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The objective of this work is to develop CuCl@AC adsorbent with high CO capacity and selectivity from CO/N 2 binary gas mixture. A series of CuCl@AC adsorbents were prepared by a solid-state auto dispersion method, and then characterized by N 2 adsorption test, XRD and XPS. CO and N 2 adsorption isotherms on the adsorbents were measured by a volumetric method. The adsorption isotherms and selectivities of CuCl@AC adsorbents for CO/N 2 binary mixture were estimated on the basis of ideal adsorbed solution theory (IAST). Results showed that (a) CO uptakes of CuCl@AC increased with CuCl loading in the loading range of 0-1.2 g/g. The maximal CO adsorption capacity of the CuCl@AC with CuCl loading of 1.2 g/g reached 38 cc/g at the P/P 0 of 0.40, around 8 times of that over the original AC; (b) calcination time for the preparation of Cu(I)@AC had significantly impact on CO adsorption of the adsorbents due to valence change of Cu species on carbon surfaces. XPS analysis indicated that when the calcination time was optimized to be 1 h at 350°C under argon, the prepared Cu(I)@AC had the highest percentage of Cu ? species on its surfaces, and consequently it had the highest CO capacity among the adsorbents since adsorptive species responsible for CO adsorption is Cu ? ; (c) The IAST-predicted CO/N 2 adsorption selectivities of 1.2CuCl/AC decreased with pressure. Its CO/N 2 selectivity was up to 100-450 at low pressure range of 0-10 kPa, and it remained in the range of 50-100 at higher pressure range of 20-100 kPa. The high adsorption capacity and selectivity of Cu(I)@AC adsorbents made it a promising adsorbent for CO/N 2 mixture separation.

An easy pyrolysis and activation synthesis method has been proposed to convert a common biomass waste of Euonymus japonicus leaves into nitrogen-doped porous carbons (NPCs), and its application in the removal of methylene blue (MB), methylene orange (MO) and rhodamine B (RhB) from simulated wastewater was further explored. The uptake of NPCs for dyes increases along with the initial dye concentration and contact time but decreases with the NPC dosage. The adsorption capacities of the NPCs for MB, RhB and MO were 626.1, 620.7 and 370.8-1 mg•g , respectively, which meant that the NPCs were better adsorbents for cationic dyes (MB and RhB), compared to the anionic dye (MO), because the NPC surfaces carry partial negative charges. In order to elaborate the adsorption mechanism, the kinetics data were analyzed by pseudo-first order, pseudo-second order, intra-particle diffusion and Elovich models, in which the pseudo-second order model exhibited the best fit. The adsorption data were evaluated by Langmuir, Freundlich, Temkin and Dubinin-Radushkevich isotherm models, in which the Langmuir model could well describe the adsorption processes. This study presented a potential alternative low-cost high efficient adsorbent for removing pollutant dyes from wastewater through using biomass waste leaves as sources.

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