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Abstract The development of an adsorbent material by 3D printing technology with high CO 2 adsorption capacity and electrical conductivity is presented for application in Electric Swing Adsorption process. The adsorbent is composed by zeolite 13X, activated carbon and binder. The prepared ink was characterized in order to determine its rheological properties. Two honeycomb monoliths, one with 30 × 30 × 43 mm3 and another one with 30 × 28 × 10 mm3 were printed. Textural characterization was performed by several techniques, including CO 2 adsorption at 273 K. A high CO 2 adsorption capacity of 3.49 mol/kg was obtained for the 3D-printed monolith at 0.15 bar and 273 K. Mechanical strength of the material was evaluated in a piece with 10 × 10 × 4 mm3. A value of 5.0 MPa was obtained. Heating of the material was tested by Joule effect through an electric current passage in the monolith, which presented a resistivity of 0.28 Ωm. An increase of temperature of about 80 K was achieved in 180 s, with a power consumption of 3.25 W. An adsorption quantity of CO 2 of 1.45 mol/kg (at 0.09 bar and 303 K) was obtained by adsorption equilibrium isotherms measurements. These experiments demonstrated that the printed material is suitable for Electric Swing Adsorption processes applied for CO 2 capture. Graphical abstract Image 1 Highlights • 3D-Printed honeycomb monolith with 43 mm of height was successfully developed. • CO 2 adsorption isotherms demonstrated a high adsorption capacity. • A power of 3.25 W for 180 seconds is needed to increase the temperature 80 K. • 3D-printed adsorbent can be used in ESA process due to the electrical properties. [ABSTRACT FROM AUTHOR]

Dehydration is a critical operation in natural gas conditioning as it reduces the potential for corrosion, hydrate formation and freezing in process equipment and transportation pipelines. Water dew point adjustment is particularly challenging in the remote ultra-deepwater natural gas reserves of the Brazilian Pre-Salt fields due to their very high carbon dioxide contents – from 30% up to 90% in raw natural gas – which is a consequence from the carbonaceous rock of the reservoir structure and long term elevation of carbon dioxide content due to its injection for early enhanced oil recovery. Under this scenario, the study evaluates the impact of the carbon dioxide content of the natural gas on the performance of water dew point via water adsorption on 4 Å Zeolite molecular sieve beds. Process simulation with adsorption simulator Adsim (Aspen Technology, Inc), at varying operation pressures and carbon dioxide contents in raw natural gas, indicated that, although adsorption meets water removal specification in a condensation free operation, the high fugacity of carbon dioxide penalizes the dehydration performance due to probably two facts: (i) higher carbon dioxide fugacity in the humid natural gas imply higher saturation water content in the gas phase, which increases the service of dehydration units; and (ii) higher carbon dioxide fugacity in the humid natural gas establishes a discreet adsorption competition with water resulting in 6.5% increase of adsorbent bed volume for operating pressures of 35 bar or higher. [ABSTRACT FROM AUTHOR]

CPL- n porous coordination polymers (PCPs) in general exhibit concomitant structural expansion during adsorption without a sudden gate-opening feature, but implications on the practical aspects of gas separation or storage are yet to be understood. In an attempt to gain further knowledge, we have gathered CO 2 and CH 4 adsorption/desorption and fractional uptake data using Cu 2 (pzdc) 2 L ( pzdc : pyrazine-2,3-dicarboxylate) variants CPL-2 ( L : 4,4′-bipyridine) and CPL-5 ( L : 1,2-Di (4-pyridyl) ethylene). Both exhibited good affinity toward CO 2 probably because of interactions with the adsorbate permanent quadrupole moment. Adsorption and desorption of CO 2 also features hysteresis that increases in size upon an increase in the maximum pressure registered during a complete adsorption/desorption cycle. Furthermore, the size of the hysteresis increases with an increase in equilibration time interval ( t e ), suggesting that the structural expansion proceeds at a slower rate compared to the adsorption one. CO 2 heats of adsorption (max. −27 kJ mol −1 ) and desorption (max. 36 kJ mol −1 ) also reflect the aforementioned framework expansion, particularly in the case of CPL-2. Diffusion time constants calculated using a phenomenological model show hysteresis up to gas pressures of ca. 0.4 atm. The structural changes seem beneficial for the equilibrium separation of bulk quantities of CO 2 from CH 4 as evidenced by selectivity values based on the Ideal Adsorbed Solution Theory ( S IAST ∼ 6.7 avg.), which are larger than those of MOFs with similar pore dimensions. Although kinetic selectivity values are similar to that of other metal organic frameworks (MOFs), these are smaller than those of small pore zeolites. [ABSTRACT FROM AUTHOR]

A kind of typical metal-organic frameworks (MOFs) material, HKUST-1 was prepared by hydrothermal method and characterized by XRD and SEM. The results of characterizations manifested that HKUST-1 showed a regular octahedral crystal structure. The as-prepared HKUST-1 was modified by several kinds of organic base materials and the 2 adsorption behaviors of modified HKUST-1 materials were evaluated. The 2 adsorption capacities of different base modified HKUST-1 varied with the base intensity of modified organic base materials. [ABSTRACT FROM AUTHOR]