| Pressure swing adsorption (PSA) is a new gas separation technology developed in the separation industry recently. PSA is well suited to the removal and subsequent recovery of CO2 from gases due to its ease of applicability over a relatively wide range of temperature and pressure conditions and its energy efficiency. its principle is a cyclic batch process where adsorption is carried out at a relatively higher pressure and desorption (regeneration) is accomplished at a lower pressure, generally using part of the product from the adsorption step. But a key aspect in the separating is the identification of a suitable adsorbent, and the performance of absorbent influenced directly the effect of separation. In order to improve the adsorption performance of traditional zeolite adsorbent, the influence of binder in Shaping, calcination temperature, alkali treatment on the structure and adsorption property was investigated using CO2, N2, CO and CH4 as probe. The result showed that after alkali treatment both of the two shaped 13X zeolite (shaped 13X/A zeolite and shaped 13X/K zeolite) exhibit higher adsorption capacity for CO2, N2, CO and CH4, And the adsorption capacity of CO2, N2, CO and CH4 on shaped 13X/K zeolite are higher than that of shaped 13X/A zeolite. The influence of NaOH treatment on the crystal and pore structure was examined by XRD and N2 adsorption-desorption (77K), and The possible mechanism for alkali treatment was also discussed. Results present that after the treatment of alkali solution, shaped 13X/A zeolite exhibits higher crystallinty, larger micropore surface area and volume compared with the origin sample. And such change improves the adsorption capacity of shaped 13X/A zeolite for CO2, N2, CO and CH4 evidently. The dissolution of some amorphous species in shaped 13X/A zeolite into NaOH solution may be responsible for the higher crystallinity and larger surface area of treated shaped 13X/A zeolite. However, treated shaped 13X/K zeolite not only shows even more higher crystallinty compared to the starting sample, but also have some characteristic XRD peak of zeolite A, the results indicate that some kaolin in shaped 13X/K zeolite transform into zeolite in the process of alkali treatment, and this may be responsible for the higher crystallinity and larger surface area of treated shaped 13X/K zeolite. And such changes improve the adsorption capacity of the shaped 13X/K zeolite for CO2, N2, CO and CH4 adsorption properties of shaped zeolite X adsorbent, and modification of zeolite X were investigated.Zeolite 13X were shaped using attapulgite (13X/A), the adsorption properties of the samples were investigated. And the adsorption performance of shaped 13X zeolite with attapulgite and that with kaolin(13X/K) was also compared. Results show that owing to the unique pore structure and large surface area, attapulgite has additional effect of improving adsorption capacity of shaped 13X/A zeolite in addition to hindering. In the range of calcination temperature investigated, the surface area and pore volume of shaped 13X/A zeolite reach the optimum value at 823.15K, and then decrease with the further increase of temperature. According to the change of surface area and pore volume, the shaped 13X/A zeolite calcined at 823.15K also show the largest adsorption capacity for CO2 and H2O. when calcined at 823.15K, shaped 13X/A zeolite have higher adsorption capacities. The adsorption capacity of shaped 13X/A zeolite for CO2, N2, CO and CH4 is 105.80ml/g, 5.93ml/g, 12.34 ml/g and 10.59 ml/g respectively, and enhanced 2.95 ml/g, 0.19ml/g , 2.06ml/g and 1.55 ml/g comparing with shaped 13X/K zeolite, exhibiting the higher adsorption capacity.In the purpose of enhancing its adsorption performance, the two kinds of shaped 13X zeolite (shaped 13X/A zeolite and shaped 13X/K zeolite) were treated by certain concentration of NaOH solution. The influence on evidently.For further enhancing adsorption performance of X zeolite, in this paper, zeolite X were desilicated with aqueous solutions of NaOH and Na2CO3, and also were realuminated with aqueous solusions of NaOH and Na2CO3 and NaAlO2. The products were characterized by using X-ray diffraction, N2 adsorption-desorption (77K) and Fourier Transformer Infrared Spectroscopy et al. After thus treatment, the influence on adsorption property were also investigated using CO2,N2 and CO. The result showed that after thus treatment zeolite X exhibit higher adsorption capacity for CO2, N2 and CO. and larger micropore surface area and volume compared with the starting sample.
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