A novel method utilizing hydrocolloids to prepare nicely shaped spheres of metal-organic frameworks (MOFs) has been developed. Microcrystalline CPO-27-Ni particles are dispersed in either alginate or chitosan solutions, which are added dropwise to solutions containing, respectively, either divalent group 2 cations or base that act as gelling agents. Well-shaped spheres are immediately formed, which can be dried into spheres containing mainly MOF (>95 wt %). The spheronizing procedures have been optimized with respect to maximum specific surface area, shape, and particle density of the final sphere. At optimal conditions, well-shaped 2.5-3.5 mm diameter CPO-27-Ni spheres with weight-specific surface areas <10 % lower than the nonformulated CPO-27-Ni precursor, and having sphere densities in the range 0.8 to 0.9 g cm(-3) and particle crushing strengths above 20 N, can be obtained. The spheres are well suited for use in fixed-bed catalytic or adsorption processes.

Metal-Organic Frameworks (MOFs) thanks to their Type V water adsorption isotherm (“S-Shape”) and large water capacity are considered as potential breakthourgh adsorbents for heat-pump applications. In particular Al(OH)-fumarate could enable...

Well-shaped 300−700 μm spheres of aggregated metal−organic framework CPO-27-Ni crystallites have been produced using a spray-granulation method with cross-bonded alginate as the binder. The spheres are suitable for use in a moving-bed temperature-swing adsorption (MBTSA) process for postcombustion CO 2 capture. The adsorption isotherm data of CO 2 , N 2 ,and H 2 O have been measured in the temperature intervalof 30−120 °C, and adsorption kinetics have been estimated from breakthrough measurements. The adsorption data together with the physical characteristics of the spheres (pore-size distribution and porosity) have been used to simulate the performance of a MBTSA process utilizing the CPO-27-Ni/alginate spheres as adsorbent and compared to similar simulations using Zeolite 13X spheres. Simulations have been carried out in a natural gas-fired power plant (NGCC) context. The process simulations indicate that the net electric efficiency of the NGCC plant with a MBTSA process utilizing the CPO-27-Ni/alginate spheres is similar to that of a MBTSA process utilizing Zeolite 13X adsorbent, 56.1% and 55.9%, respectively, which are slightly higher than the net efficiency of the benchmark case NGCC with a MEA-based solvent process of 54.7%.

Shaping of metal-organic frameworks into macro-structured particles for reactors and separation processes is a fundamental step in their way towards commercialization. Extrusion techniques which are used for shaping many porous materials resulted in significant reduction of surface area in many MOF materials and thus alternative techniques are required. One alternative way to shape soft materials is to use a technique coming from molecular gastronomy and biology; the calcium alginate method.For this method, a slurry of the porous material and sodium alginate is prepared and then dropwise put in contact with calcium chloride solution forming spheres. Forming particles with both suitable diffusion and mechanical properties and without significant reductions in surface area, many operating variables must be tuned and optimized. This publication presents the results obtained showing the effects of varying all the process variables of the alginate method for shaping UiO-66 MOF.Characterization in terms of surface area and other surface methods, force required to break particles (crushing strength) and measurement of isotherms of carbon dioxide. With this method we have produced MOF particles with crushing strength similar to alumina or silica) and with only 10% of reduction in surface area and adsorption capacity.

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