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Metal–organic frameworks (MOFs) currently receive high interest for cycling water adsorption applications like adsorption heat transformation for air-conditioning purposes. For practical use in adsorption heat pumps (AHPs), the microcrystalline powders must be formulated such that their high porosity and pore accessibility are retained. In this work, the preparation of millimeter-scaled pellets of MIL-160­(Al), Al-fumarate (Basolite A520), UiO-66­(Zr), and Zr-fumarate (MOF-801) is reported by applying the freeze granulation method. The use of poly­(vinyl alcohol) (PVA) as a binder reproducibly resulted in highly stable, uniformly shaped PVA/MOF pellets with 80 wt % MOF loading, with essentially unchanged MOF porosity properties after shaping. The shaped pellets were analyzed for the application in AHPs by water adsorption isotherms, over 1000 water adsorption/desorption cycles, and thermal and mechanical stability tests. Furthermore, the Al-fum pellets were applied in a fixed-bed, full-scale heat exchanger, yielding specific cooling powers from 349 up to 431 W/kg (adsorbent), which outperforms the current commercially used silica gel grains in AHPs under comparable operating conditions.

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Surface halogenation is an important means to tune or improve functionalities of solid-state materials. However, this concept has been hardly explored and exploited in the engineering of metal-organic frameworks (MOFs). Here, a facile approach to obtain halo-functionalized derivatives of zirconium fumarate (MOF-801) is developed by reacting zirconium halides (ZrX4; X = Cl, Br, I) in water with acetylenedicarboxylic acid. The latter quantitatively undergoes an unusual in situ linker transformation into halofumarate via trans addition of HX to the −CC– triple bond. This HX addition and MOF formation happen in a one-pot reaction, that is, the in situ generated halogenated linker reacts with zirconium ions in solution to yield three microporous HHU-2-X MOFs (X = Cl, Br, I) with an fcu topology, containing UiO-type [Zr6O4(OH)4] secondary building units 12-fold connected by halofumarate linkers. The halogen (Cl) groups in HHU-2-Cl result in increased hydrophilicity for water vapor sorption as well as increased gas uptakes of 21% SO2, 24% CH4, 44% CO2, and 154% N2 when compared to the non-halogenated MOF-801. The tuning of the inner surface chemistry is realized to yield multipurpose adsorbent materials for enhanced gas and vapor uptakes over their non-halogenated analogues. The gas sorption properties of the chlorinated HHU-2-Cl material indicate its suitability for CO2, N2, and SO2 capture and separation, while its water sorption profile yields a high heat storage capacity of 500 kJ kg–1, making it promising for adsorption-based thermal batteries and dehumidification applications.

Background: In the last decades, 3D-printing has been investigated and used intensively in the field of tissue engineering, automotive and aerospace. With the first FDA approved printed medicinal product in 2015, the research on 3D-printing for pharmaceutical application has attracted the attention of pharmaceutical scientists. Due to its potential of fabricating complex structures and geometrics, it is a highly promising technology for manufacturing individualized dosage forms. In addition, it enables the fabrication of dosage forms with tailored drug release profiles. Objective: The aim of this review article is to give a comprehensive overview of the used 3D-printing techniques for pharmaceutical applications, including information about the required material, advantages and disadvantages of the respective technique. Methods: For the literature research, relevant keywords were identified and the literature was then thoroughly researched. Conclusion: The current status of 3D-printing as a manufacturing process for pharmaceutical dosage forms was highlighted in this review article. Moreover, this article presents a critical evaluation of 3D-printing to control the dose and drug release of printed dosage forms.

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