Metal-organic framework materials for adsorption heat pumps

Al-Dadah, Raya; Mahmoud, Saad; Elsayed, Eman; Youssef, Peter G.; Al-Mousawi, Fadhel Noraldeen

doi:10.1016/j.energy.2019.116356

Cited by 67 publications

(39 citation statements)

References 26 publications

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“…Metal–organic frameworks (MOFs) based on a triiron oxo-centered cluster (Fe 3 O) 1 , 2 are important materials for several applications, including gas storage and separation, 3 − 5 heat pump applications, 6 , 7 catalysis, 8 − 10 and drug delivery. 1 , 11 , 12 The most representative of this class of MOFs are MIL-100(Fe) 2 and MIL-101(Fe) (MIL = Materials Institute Lavoisier).…”

Section: Introductionmentioning

confidence: 99%

Thermal Treatment Effect on CO and NO Adsorption on Fe(II) and Fe(III) Species in Fe₃O-Based MIL-Type Metal–Organic Frameworks: A Density Functional Theory Study

Vitillo

Gagliardi

2021

Inorg. Chem.

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The properties of metal–organic frameworks (MOFs) based on triiron oxo-centered (Fe 3 O) metal nodes are often related to the efficiency of the removal of the solvent molecules and the counteranion chemisorbed on the Fe 3 O unit by postsynthetic thermal treatment. Temperature, time, and the reaction environment play a significant role in modifying key features of the materials, that is, the number of open metal sites and the reduction of Fe(III) centers to Fe(II). IR spectroscopy allows the inspection of these postsynthetic modifications by using carbon monoxide (CO) and nitric oxide (NO) as probe molecules. However, the reference data sets are based on spectra recorded for iron zeolites and oxides, whose structures are different from the Fe 3 O one. We used density functional theory to study how the adsorption enthalpy and the vibrational bands of CO and NO are modified upon dehydration and reduction of Fe 3 O metal nodes. We obtained a set of theoretical spectra that can model the modification observed in previously reported experimental spectra. Several CO and NO bands were previously assigned to heterogeneous Fe(II) and Fe(III) sites, suggesting a large defectivity of the materials. On the basis of the calculations, we propose an alternative assignment of these bands by considering only crystallographic iron sites. These findings affect the common description of Fe 3 O-based MOFs as highly defective materials. We expect these results to be of interest to the large community of scientists working on Fe(II)- and Fe(III)-based MOFs and related materials.

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Section: Introductionmentioning

confidence: 99%

Thermal Treatment Effect on CO and NO Adsorption on Fe(II) and Fe(III) Species in Fe₃O-Based MIL-Type Metal–Organic Frameworks: A Density Functional Theory Study

Vitillo

Gagliardi

2021

Inorg. Chem.

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“…These techniques make it possible to design cooling units with improved power densities, [11] [12]. Other recent studies show that the use of directed mass transfer channels [13] [14] or structures with metal organics [15] [16] [17] in the adsorber bed make it possible to capitalize the heat and mass transfers. Other authors study the thermodynamic cycles of the different adsorption couples of a solar cooling machine, [18] [19].…”

Section: Introductionmentioning

confidence: 99%

Study of Habitat’s Thermal Performance Equipped with an Adsorption Cooling Unit by Geothermal Heat Pump

El-Maktoume¹,

Chesneau²,

Diallo³

et al. 2021

JPEE

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This work concerns a modeling of habitat equipped with an adsorption cooling unit powered by a geothermal heat pump in the context of the climate of the Comoros Islands. Cooling unit is a simple system consisting of an adsorber, condenser and evaporator. The modeling of the habitat-air conditioning system was based on a description of heat and mass transfers. The first law of thermodynamics on the energy conservation using the analogies between heat and electrical transfers is used to establish the equations of the model. Zeolite-methanol pair and Dubinin-Astakhov adsorption model are used to describe the amount of adsorbed mass. The finite difference method applied to a point of the considered exchange surface is used to discretize equations and resolve them. The coupling of the system takes place through a convective transfer between the air inside habitat and the evaporator's surface. This article presents results for typical November days in Comoros. Different temperatures of habitat with and without a cooling unit show that using the adsorption cooling unit can help lower internal temperatures. We observe a temperature difference of 2.14 K in particular at 2 p.m., if the air conditioning starts at 8 a.m. The influence of the input parameters on the air inside the habitat makes it possible to assess the impact on indoor comfort. The COP th can reach 0.46. However, we can get a high performance if we optimize temperature thresholds. These show that this type of cooling unit can help improve the habitat thermal comfort in a tropical and dry climate.

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“…The research for new adsorbent materials with enhanced characteristics and new adsorber designs are important for further advancements in AHP technology and have recently been the focus of several studies [21][22][23]. On the other hand, system-level studies involving models that deal with all the components of an AHP system are lacking in the literature [24].…”

Section: Introductionmentioning

confidence: 99%

Modeling and Analysis of a Coated Tube Adsorber for Adsorption Heat Pumps

Dias

Costa

2021

Energies

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This work investigates the effects of several parameters on the coefficient of performance (COP) and the specific heating power (SHP) of a coated-tube adsorber for adsorption heat pumps (AHP) suitable for water heating (space and/or domestic water heating). The COP and SHP are obtained based on physical models that have already been proven to adequately describe this type of adsorber. Several parameters are tested, namely, the regeneration, condenser and evaporator temperatures, the heat transfer fluid velocity, the tube diameter, the adsorbent coating thickness, the metal–adsorbent heat transfer coefficient, and the cycle time. Two different scenarios were tested, corresponding to distinct working conditions. The working conditions for Scenario A are suitable for pre-heating water in mild climates. Scenario B’s working conditions are based on the European standard EN16147. The maximum COP is obtained for regeneration temperatures of 75 °C and 95 °C for Scenarios A and B, respectively. The COP increases for longer cycle times (more complete adsorption and desorption processes) whilst the SHP decreases (less complete cycles by unit time). Hence, the right balance between the COP and the SHP must be found for each particular scenario to have the best whole performance of the AHP. A metal–adsorbent heat transfer coefficient lower than 200 W·m−2·K−1 leads to reduced SHP. Lower adsorbent coating thicknesses lead to higher SHP and can still provide reasonably high COP. However, low coating thicknesses would require a too-high number of tubes to achieve the desired adsorbent mass to deliver the required useful heating power, resulting in too-large systems. Due to this, the best relationship between the SHP and the size of the system must be selected for each specific application.

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Metal-organic framework materials for adsorption heat pumps

Cited by 67 publications

References 26 publications

Thermal Treatment Effect on CO and NO Adsorption on Fe(II) and Fe(III) Species in Fe₃O-Based MIL-Type Metal–Organic Frameworks: A Density Functional Theory Study

Thermal Treatment Effect on CO and NO Adsorption on Fe(II) and Fe(III) Species in Fe₃O-Based MIL-Type Metal–Organic Frameworks: A Density Functional Theory Study

Study of Habitat’s Thermal Performance Equipped with an Adsorption Cooling Unit by Geothermal Heat Pump

Modeling and Analysis of a Coated Tube Adsorber for Adsorption Heat Pumps

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Metal-organic framework materials for adsorption heat pumps

Cited by 67 publications

References 26 publications

Thermal Treatment Effect on CO and NO Adsorption on Fe(II) and Fe(III) Species in Fe3O-Based MIL-Type Metal–Organic Frameworks: A Density Functional Theory Study

Thermal Treatment Effect on CO and NO Adsorption on Fe(II) and Fe(III) Species in Fe3O-Based MIL-Type Metal–Organic Frameworks: A Density Functional Theory Study

Study of Habitat’s Thermal Performance Equipped with an Adsorption Cooling Unit by Geothermal Heat Pump

Modeling and Analysis of a Coated Tube Adsorber for Adsorption Heat Pumps

Contact Info

Product

Resources

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Thermal Treatment Effect on CO and NO Adsorption on Fe(II) and Fe(III) Species in Fe₃O-Based MIL-Type Metal–Organic Frameworks: A Density Functional Theory Study

Thermal Treatment Effect on CO and NO Adsorption on Fe(II) and Fe(III) Species in Fe₃O-Based MIL-Type Metal–Organic Frameworks: A Density Functional Theory Study