Fumarate Metal Organic Framework Research Articles

Green composite synthesis based on aluminum fumarate metal-organic framework (MOF) for doxorubicin delivery: An in vitro study

The development of an eco-friendly and cost-effective drug delivery system (DDS) remains a challenge in cancer treatment. This study suggests a novel, eco-friendly, and cost-effective method to synthesize aluminum fumarate (A520) MOF using tangerine peel extract (TPE) as a pH-sensitive coating agent on a reduced graphene oxide (rGO) substrate. The system also incorporates the 2,2′-bipyridine dimethyltin diisothiocyanate complex, (Sn(bpy), as an organotin complex) to enhance therapeutic efficacy while minimizing off-target effects. In vitro cellular and molecular cytotoxicity examinations were conducted using HEK-293 and MCF-7 cell lines to evaluate cytotoxicity after 24 and 72 h. The findings of the MTT assay indicated that the final nanocarriers, without and with doxorubicin (DOX), exhibited relative cell viability of 95 % and 55 %, respectively, highlighting the system's potential for efficient and safe drug delivery. The TPE coating created a pH-sensitive DDS with high drug loading efficiency (DLE) (59.1 %) and low cytotoxicity. Drug release was studied over 200 h at pH 5.5 and 7.2. The augmented drug release profile (47 %) demonstrated a targeted release and successful inhibition of premature release in acidic environments due to pH-sensitive TPE molecules. The efficacy of targeted drug delivery to the MCF-7 cell was evaluated using 2D fluorescence microscopy, which demonstrated successful delivery of drugs to the cells. This innovative approach addresses the limitations of existing studies while promoting biocompatibility, stability, and functionality in DDSs.

Ligand extension of aluminum fumarate metal-organic framework in transferring higher water for adsorption desalination

Ligand extension of aluminum fumarate metal-organic framework in transferring higher water for adsorption desalination

Enhanced fluoride removal using montmorillonite clay modified with CoFe2O4 and metal-organic frameworks

The use of modified clays can play an effective role as an effective adsorbent in removing fluoride (Flu) ions from water and aqueous solutions. In the present research, montmorillonite clay (MMt) was modified using CoFe2O4 magnetic particles and Al–Fe fumarate metal-organic framework (Al–Fe Fum) and was utilized as an efficient adsorbent for removing Flu from aqueous solution. The properties of MMt and MMt/CoFe2O4/Al–Fe Fum samples were investigated using different techniques. The results showed that with the modification of MMt using CoFe2O4 magnetic particles and the metal-organic framework of Al–Fe Fum, the BET surface has increased notably from 13.217 to 365.80 m2/g. To investigate the effect of independent variables and their interaction on the efficiency of the Flu adsorption, response surface method-central compound design (RSM-CCD) was served. Based on the results of ANOVA, the F-value and p-value parameters for the desired model were determined to be 783.09 and < 0.0001, respectively, which confirms the success and high ability of the model. The number of R2, adjusted R2, and Predicted R2 for adsorption of Flu ion was determined to be 0.998, 0.997, and 0.995, respectively, which shows that the proposed regression model can describe the process of adsorption and interaction between variables well. Compared to other kinetic models, the pseudo 2nd order kinetic model has a greater ability to describe the Flu adsorption behavior. The R2 parameter value determined that the Freundlich isotherm model has a suitable ability to investigate the isotherm behavior and confirms the effect of heterogeneous surfaces in the process. Generally, the outcomes signified that the MMt and MMt/CoFe2O4/Al–Fe Fum samples can be reused several times in the process of Flu adsorption, while the efficiency is more than 90%.

Unraveling the Mechanisms of Zirconium Metal–Organic Frameworks‐Based Mixed‐Matrix Membranes Preventing Polysulfide Shuttling

Lithium–sulfur batteries are considered as promising candidates for next‐generation energy storage devices for grid applications due to their high theoretical energy density. However, the inevitable shuttle effect of lithium polysulfides and/or dendrite growth of Li metal anodes hinder their commercial viability. Herein, the microporous Zr fumarate metal–organic framework (MOF)‐801(Zr) is considered to produce thin (≈15.6 μm, ≈1 mg cm2) mixed‐matrix membranes (MMM) as a novel interlayer for Li–S batteries. It is found that the MOF‐801(Zr)/C/PVDF‐HFP composite interlayer facilitates Li+ ions diffusion, and anchors polysulfides while promoting their redox conversion effectively. It is demonstrated that MOF‐801 effectively trapped polysulfides at the cathode side, and confirmed for the first time the nature of the interaction between the adsorbed polysulfides and the host framework, through a combination of solid‐state nuclear magnetic resonance and molecular dynamics simulations. The incorporation of MOF‐801(Zr)/C/PVDF‐HFP MMM interlayer results in a notable enhancement in the initial capacity of Li–S batteries up to 1110 mA h g−1. Moreover, even after 50 cycles, a specific capacity of 880 mA h g−1 is delivered.

Enhanced visible-light-active MOF-based PbO photocatalyst for binary dye decolorization: A comprehensive study

Developing efficient and sustainable wastewater treatment technologies like photocatalysis is essential to combating global water pollution. Despite lead oxide's photocatalytic potential, its high recombination rate and low active sites restrict its application. In the current study, the first MOF-based PbO nanostructure has been successfully synthesized in a facile way. The as-synthesized sample, PbO/Aluminum fumarate metal–organic framework (PbO/AlFu), was characterized in multiple manners and applied to degrade mixtures of methyl green (MeG) and crystal violet (CV) dyes under visible light irradiation. The incorporation of AlFu metal–organic framework as a support for PbO significantly enhanced photo-degradation performance. This enhancement can be attributed to the increased visible light harvesting, adsorption capabilities facilitated by AlFu, and separation of photo-generated electron-hole pairs due to the formation of the step-scheme (S-scheme) heterojunction. Photocatalytic efficiencies and operational parameters were modeled and optimized respectively using the Box-Behnken design (BBD). Under optimized conditions, MeG and CV dyes were removed at 95.6 and 86.1 percent, respectively. •O2– and •OH radicals were identified as key contributors to the photo-degradation of both dyes. Kinetic studies revealed that photo-degradation of both dyes followed the Langmuir-Hinshelwood model, suggesting a surface-mediated reaction mechanism. PbO/AlFu demonstrated outstanding stability and reusability in five sequential photo-degradation cycles. The present findings highlight the potential of PbO/AlFu as a promising photocatalyst for wastewater treatment.

Sulfate ion induced formation of unsaturated coordination of AlF3 nanocluster catalyst confined in carbon framework for catalytic dehydrofluorination

The gas-phase catalytic dehydrofluorination of hydrofluorocarbons (HFCs) to produce hydrofluoroolefins is an important strategy for the resource utilization of HFCs. AlF3 is the most suitable and efficient catalyst for dehydrofluorination of HFCs. However, sintering and preservation of coordinatively unsaturated aluminum centers pose significant challenges for AlF3 catalysts. Herein, we prepared carbon-confined AlF3 nanocluster catalysts with aluminum fumarate metal organic frameworks (AlFu-MOF) as the precursors, followed by carbonization and fluorination treatments. During catalyst preparation, anion ligand in the aluminum salt plays a major role in the formation of coordinatively unsaturated Al centers. Compared with Al(NO3)3·9H2O and AlCl3·6H2O, AlFu-MOF (named AlFu-S) prepared with Al2(SO4)3·18H2O exhibits a higher concentration of Al-OH species. Additionally, the residual SO42- ions can indeed retard the crystallization of AlF3 at elevated temperatures. Hence, the decomposition of Al-OH groups and the presence of residual SO42- ions in AlFu-S contribute together to the abundance of unsaturated coordinated Al centers in the finally carbon-confined AlF3 nanocluster catalyst (named AlFu-S-550-F). Also, the confinement effect of the carbon material formed by the carbonization of AlFu-S effectively prevent AlF3 nanocluster from sintering and phase transition, hence, in the dehydrofluorination of HFC-134a, AlFu-S-550-F demonstrates excellent stability compared to AlF3 catalysts prepared by precipitation methods. In summary, this study provides a strategy for the preservation of coordinatively unsaturated aluminum centers in AlF3 catalysts due to sintering and crystal structure transformation. Furthermore, the methodology proposed in this work is also applicable to the preparation of other coordinatively unsaturated metal catalysts.

A Functionally Asymmetric Janus Hygro-Photothermal Hybrid for Atmospheric Water Harvesting in Arid Regions.

Metal-organic frameworks (MOFs) are high-performance adsorbents for atmospheric water harvesting but have poor water-desorption ability, requiring excess energy input to release the trapped water. Addressing this issue, a Janus-structured adsorbent with functional asymmetry is presented. The material exhibits contrasting functionalities on either face - a hygroscopic face interfaced with a photothermal face. Hygroscopic aluminum fumarate MOF and photothermal CuxS layers are in-situ grown on opposite sides of a Cu/Al bimetallic substrate, resulting in a CuxS-Cu/Al-MOF Janus hygro-photothermal hybrid. The two faces serve as independent "factories" for photothermal conversion and water adsorption-desorption respectively, while the interfacing bimetallic layer serves as a "heat conveyor belt" between them. Due to the high porosity and hydrophilicity of the MOF, the hybrid exhibits a water-adsorption capacity of 0.161g g-1 and a fast adsorption rate (saturation within 52min) at 30% relative humidity. Thanks to the photothermal CuxS, the hybrid can reach 71.5 °C under 1 Sun in 20min and desorb 97% adsorbed water in 40min, exhibiting a high photothermal conversion efficiency of over 90%. CuxS-Cu/Al-MOF exhibits minimal fluctuations after 200 cycles, and its water-generation capacity is 3.21 times that of powdery MOF in 3 h in a self-designed prototype in one cycle.

An effective approach for CH4/N2 separation using aluminum-based metal-organic frameworks (MOFs) prepared from coal fly ash

Metal-organic frameworks (MOFs) are considered one of the promising adsorbents for CH4/N2 separation. However, MOFs commercialization is a big challenge since their synthetic materials are expensive and not environmentally friendly. Herein, the dealumination solution obtained from coal fly ash (CFA) using sulfuric acid as an extracting agent through direct leaching and roasting technologies was applied as metal feedstock to prepare CFAx-FumMOF-y and compared to aluminum fumarate MOF (Al-FumMOF) in morphology, surface area, micropore volume, and CH4/N2 selective separation. The results indicated that CFAx-FumMOF-y exhibited closely similar surface area (1164.94–1073.08 m2/g) and micropore volume (0.40–0.36 cm3/g) to Al-FumMOF (1287.55 m2/g, 0.42 cm3/g), even there were no detectable differences in CH4 uptakes (CFAx-FumMOF-y, 21.93–20.69 cm3/g; Al-FumMOF, 22.13 cm3/g) at 298 K and 1.0 bar, suggesting that the impurity metal species in dealumination solution hardly affect textural properties and gas uptakes. Moreover, the isosteric heat of adsorption (Qst) and IAST CH4/N2 selectivity of CFAs-FumMOF-1 (19.25–17.84 kJ/mol) and CFAb-FumMOF-1 (18.83–18.64 kJ/mol) were slightly superior to Al-FumMOF (17.83.64–16.86 kJ/mol, 4.87), suggesting that CFAx-FumMOF-1 played an identical role as Al-FumMOF in gases separation. The cyclic regeneration experiments and binary breakthrough tests further confirmed that CFAx-FumMOF-y was feasible for practical application. This study provides a new perspective for reducing the production cost of MOFs as well as realizing high-value utilization of CFA.

Fumarate metal organic frameworks as reactive and curing reaction alternant in hydrophobic bispropargyl ether based matrix resin system

Fumarate metal organic frameworks as reactive and curing reaction alternant in hydrophobic bispropargyl ether based matrix resin system

Facile synthesis of Aluminium fumarate metal–organic framework and hydroxyapatite composite with improved adsorption characteristics for efficient fluoride removal from water

An aluminium fumarate (AlFu)-hydroxyapatite (HAP) composite (AlFu-HAP) with numerous functional groups for fluoride binding was synthesised by a simple solid–solid mixing process. The produced AlFu-HAP composite with numerous functional groups results in outstanding adsorption capability in the sequence AlFu-HAP > AlFu > HAP. This composite was studied under different pH, initial fluoride concentrations, temperatures, and contact times. The adsorption kinetics and isotherms were pseudo-second-order model and Freundlich adsorption isotherm, respectively. XRD, SEM, FTIR, Raman spectroscopy, and XPS analysis of the samples before and after the adsorption reaction indicate that the fluoride removal mechanism was controlled by anion exchange of the OH– group in AlFu-HAP and F- in water. At high concentrations (150–200 mg F-/L) in groundwater and industrial effluent, the AlFu-HAP showed > 90 % fluoride removal. Thus, the current study will provide an effective strategy for developing an AlFu-HAP composite adsorbent to be used for the effective elimination of fluoride from wastewater.

Synthesis and characterization of α-Fe2O3 nanoplates/aluminum fumarate metal-organic framework nanosheets as a nanocarrier for anticancer drug

α-Fe2O3 nanoplates/Aluminum Fumarate metal-organic framework (α-Fe2O3/AlFu) nanocarriers were successfully synthesized through a facile hydrothermal method and used as a drug delivery system (DDS). 5-Fluorouracil (5-Fu) as an anticancer drug was incorporated into the nanocarriers through plunging in the drug solution (5-Fu/α-Fe2O3/AlFu). The developed nanocarriers, including AlFu, α-Fe2O3/AlFu, and 5-Fu/α-Fe2O3/AlFu, were well-characterized which confirmed their successful synthesis. The electron microscopy images indicated that the flower shape of AlFu MOF with an average diameter of 500 nm was decorated with the α-Fe2O3 nanoplates. The flower of AlFu was formed by some nanosheets with a diameter of 20 nm. The average diameter of the nanoplates of α-Fe2O3 was about 200 nm. The α-Fe2O3 nanoplates fell apart from the AlFu flower and were located on the nanosheets of AlFu. The nanocarriers with high surface areas were found to be proper support for loading the 5-Fu drug. The vibrating sample magnetometer (VSM) results revealed that 5-Fu/α-Fe2O3/AlFu nanocarriers retained superparamagnetic properties when embedded with α-Fe2O3 nanoplates. Results represent the better loading efficiency of the α-Fe2O3/AlFu nanocarriers (65 %) compared to its components. To demonstrate the efficiency of 5-Fu/α-Fe2O3/AlFu as novel nanocarriers for controlled release of 5-Fu, in-vitro drug delivery tests were carried out in a simulated normal (pH = 7.4 and T = 37.4 °C) and tumor (pH = 5 and T = 42 °C) tissues’ environment. It was shown that low drug release (59.8 %) occurred at neutral pH and that more than 88.8 % of the loaded drug was released at the condition of cancer cells. Temperature and pH stimulate 5-Fu release from nanocarriers. Under cancer cells conditions, the release kinetic follows the Weibull distribution model, while in normal cells conditions, the Korsmeyer-Peppas model is used. Notably, the MTT test established that the α-Fe2O3/AlFu nanocarriers have no toxicity against BT-20 breast cancer cells.

Thermodynamic Analysis and Performance Assessment of a Novel Solar-Based Multigeneration System for Electricity, Cooling, Heating, and Freshwater Production

Abstract This study offers a comprehensive assessment of the thermodynamic performance of a novel solar-based multigeneration system, which caters to the energy needs of a sustainable community by producing electricity, cooling, heating, and freshwater. The solar-based multigeneration system is comprised of four main components: the thermal subsystem of the parabolic trough collector (PTC) employing CO2 as a heat transfer fluid, a single-effect absorption refrigeration cycle (ARC), a supercritical CO2 (S-CO2) cycle, and an adsorption desalination (AD) cycle with heat recovery employing aluminum fumarate metal–organic framework (MOF) adsorbent material. A comprehensive parametric study was performed on the proposed solar-based multigeneration system by varying key parameters to evaluate its performance. It is found that the thermal and exergy efficiencies of a PTC were evaluated to be 68.35% and 29.88%, respectively, at a fixed inlet temperature of 225 °C and solar irradiation of 850 W/m2 and also a slight reduction in the ARC cycle when examining the variation in the thermal and exergetic COPs for the generator temperature. Additionally, the thermal and exergy efficiencies of electricity, cooling, and heating were determined to be 20.41% and 21.93%, 41.34% and 3.51%, and 7.14% and 3.07%, respectively, at the operating condition. The maximum specific daily water production (SDWP) value of 12.91 m3/ton/day and a gain output ratio (GOR) of 0.64 were obtained under steady operating conditions in the AD cycle.

Development and assessment of a novel integrated system powered by parabolic trough collectors for combined power, heating and freshwater production

Abstract Hybrid solar-based integrated systems represent a viable solution for countries with abundant solar radiation, as they provide energy needs in an environmentally friendly way, offering a sustainable and economically advantageous energy solution that utilizes a free source of energy. Therefore, this research offers a thermodynamic evaluation of a novel integrated system driven by solar energy that aims to produce power, heating and freshwater. The integrated system consists of a parabolic trough collector that uses CO2 as its working fluid and implements the supercritical carbon dioxide cycle to generate power and heating. The integrated system also includes an adsorption desalination system with heat recovery between the condenser and evaporator, which employs a cutting-edge material called an aluminium fumarate metal–organic framework to produce fresh water. For the modelling of a novel system, an engineering equation solver, which is considered a reliable tool for thermodynamic investigations, is employed. The effectiveness of an integrated system is evaluated using a mathematical model and different varying parameters are examined to ascertain their influence on thermal and exergy efficiency, specific daily water production and gained output ratio. The results revealed that the parabolic trough collector achieved a thermal efficiency of 67.2% and an exergy efficiency of 41.2% under certain conditions. Additionally, the thermal efficiencies for electrical and heating were obtained 24.68% and 9.85%, respectively. Finally, the specific daily water production was calculated, showing promising results and an increase from 7.1 to 12.5 m3/ton/day, while the gain output ratio increased from 0.395 to 0.62 when the temperature of hot water increased from 65°C to 85°C, under the selected conditions.

Enhanced photo-degradation of organic contaminants on CdS/magnetic aluminum fumarate metal-organic framework as a novel Z-scheme photocatalyst under visible light: A comprehensive study

In the current study, Fe3O4/aluminum fumarate (AlFu) magnetic nanocomposite has been synthesized through the sol-gel procedure to be used as a novel support for CdS nanorods in photocatalytic degradation of Congo red (CR) and crystal violet (CV) dyes in aqueous media under visible light irradiation, separately. The CdS nanorods were solvothermally decorated on magnetic AlFu. The physicochemical properties of the synthesized samples were examined by multiple techniques. In comparison to pure CdS, the photocatalytic performance of magnetical separable Cd/magnetic AlFu is striking. This could be attributed to improving the recombination rate, charge transfer resistance, and adsorption site, which are figured out through characterization data. Removal of contaminants has been statistically optimized and modeled based on operational parameters, including catalyst dosage, initial dye concentration, and pH. At optimum conditions, the removal of CR and CV dyes was 99.5 % and 86.17 %, respectively. Moreover, the photocatalyst exhibited satisfactory performance in TOC removal and remarkable stability during six successive cyclic operations. At several dye concentrations, kinetic experiments have been undertaken, and results revealed that the photo-degradation reaction of CR and CV corresponds well with the Langmuir-Hinshelwood model. Furthermore, the Z-scheme mechanism was suggested based on characterization data and quenching experiments, which revealed that •O2- plus h+ in CR photo-degradation, and •O2- plus •OH in CV photo-degradation play pivotal roles.

Zirconium fumarate metal-organic framework: a selective adsorbent for fluoride from industrial wastewater

Abstract Many industrial processes produce high fluoride (150–450 mg/L) containing effluent. It may be recovered from the processing plants at the source. One effective technology is selective fluoride adsorption from the waste stream. Metal-organic frameworks (MOFs) are crystalline compounds with high surface area, pore volume, and tuneable pore channels and are suitable adsorbents. This study used zirconium fumarate (ZrFu) MOF to recover the fluoride from iron and steel industrial wastewater collected from blast furnaces and coke plants, respectively. In batch experiments, complete fluoride uptake from synthetic water (150 mg F/L) was obtained with 3 g ZrFu/L (qe = 49.66 mg/g), while for blast furnace (170 mg F/L) and coke plant (130 mg F/L) wastewater, 10 g ZrFu/L was required, (qe = 17 mg/g) and (qe = 13 mg/g), respectively. This difference in adsorbent dose was caused by interfering ions in industrial wastewater, which compete for the same adsorption sites as fluoride ions. Chemisorption was the rate-limiting step, and it conforms to the Langmuir isotherm and the pseudo-second-order model. Fluoride desorption was achieved in deionized water in 1 h. This suggests that the adsorption–desorption process could be scaled up to an industrial process to recover and reuse fluoride from wastewater.

Gelothermal Synthesis of Monodisperse MIL-88A Nanoparticles with Tunable Sizes and Metal Centers for Potential Bioapplications.

Developing novel synthetic strategies to downsize metal-organic frameworks (MOFs) from polydisperse crystals to monodisperse nanoparticles is of great importance for their potential bioapplications. In this work, a novel synthetic strategy termed gelothermal synthesis is proposed, in which coordination polymer gel is first prepared and followed by a thermal reaction to give the monodisperse MOF nanoparticles. This novel synthetic strategy successfully leads to the isolation of Materials of Institute Lavoisier (MIL-88), Cu(II)-fumarate MOFs (CufumDMF), and Zeolitic Imidazolate Frameworks (ZIF-8) nanoparticles. Focused on MIL-88A, the studies reveal that the size can be well-tuned from nanoscale to microscale without significant changes in polydispersity index (PDI) even in the case of in situ metal substitution. A possible mechanism is consequently proposed based on extensive studies on the gelothermal condition including sol-gel chemistry, thermal condition, kinds of solvents, and so on. The unique advantages of monodisperse MIL-88A nanoparticles over polydisperse ones are further demonstrated in terms of in vitro magnetic resonance imaging (MRI), cellular uptake, and drug-carrying properties.

Forward osmosis membrane doped with water-based zirconium fumarate MOFs to enhance dye pollutant removal and membrane antifouling performance.

Metal-organic frameworks (MOFs) can be applied to enhance the property of forward osmosis membranes. However, organic solvents can easily remain in organic synthetic metal-organic frame materials and cause membrane fouling and a decrease in membrane permeability. In this study, water-based Zr-fumarate MOFs were synthesized and doped into the membrane active layer by interfacial polymerization to provide a water-based MOF-doped thin-film composite membrane (TFC membrane). It was found that doping the water-based MOFs effectively improved membrane hydrophilicity, and nanowater passages were introduced in the active layer to improve permeability. The water flux of the water-based MOF-doped TFC membranes was increased by 21% over that of the original membrane, and the selectivity performance of the membrane was improved while keeping the salt rejection basically unchanged. Additionally, the water-based MOF-doped TFC membrane showed good removal efficiency (Rd > 94%) and strong antipollution performance in the treatment of dye pollutants.

In-situ grafted amine functionalized metal-organic frameworks for CO2 capture: Preparation and bench-scale performance evaluation

The work includes the preparation of zirconium fumarate (ZrFu) metal-organic framework (MOF) and investigation of the CO2 capture performance of the material. The CO2 adsorption experiments were performed in a bench-scale flow reactor with a simulated flue gas mixture. To enhance the CO2 capture capacity of the ZrFu material, two polydentate amines, namely diethylenetriamine (DETA) and tetraethylenepentamine (TEPA) were incorporated into the ZrFu by an in-situ grafting method. The effects of adsorption temperature, pressure, amine loading, and CO2 concentration in the feed gas mixture on CO2 capture were examined. The obtained value of the CO2 uptake capacity of the pristine ZrFu is 73 g CO2/kg sorbent at 30 ºC under atmospheric pressure. Among the amine-modified MOFs, the DETA-modified ZrFu (10-DETA-ZrFu) showed a maximum adsorption capacity of 86 g CO2/kg sorbent. It is also noted that at 90 °C, the CO2 adsorption capacity of the material is 57 g CO2/kg sorbent, which is about 67% of the capture capacity at 30 °C. This demonstrates that the MOFs can capture and retain the CO2 molecules inside the MOF moiety even at higher temperatures. The study also revealed that the synthesized MOFs are chemically stable with about 10% moisture environment. The prepared MOFs exhibited admirable thermo-chemical stability up to around 150 °C. Among the studied isotherm models, the Langmuir model showed a good agreement with the experimental data for lower values of adsorption pressure. The estimated value of adsorption energy for the adsorption of CO2 on ZrFu is 6.9 kJ/mol at 30 °C.

Potential of metal-organic frameworks to adsorb ethylene for fresh produce active packaging applications

Metal-organic framework (MOF) is an innovative synthetic porous material widely used for gas storage and separation, but its applications for food packaging have barely been investigated. The objective was to evaluate MOFs’ potential to be embedded in packaging films as ethylene adsorbers to control ripening and extend the shelf life of fresh produce during distribution. The potential was evaluated at two levels. The first evaluation was at the MOF powder level, where the ethylene adsorption capacities of eight commercial MOF powders were measured using gas chromatography (GC). As a result, Mg formate MOF (MgF) and Al(OH) fumarate MOF (AlF) were found to have much higher ethylene adsorption capacities than the other six MOFs. Overall, MgF was the best ethylene adsorber due to its stable ethylene adsorption under various temperatures, relative humidities, and ethylene concentrations. The second evaluation was at the packaging film level, where MgF powder was embedded into three different packaging films. The results showed that MgF-embedded LDPE film had higher ethylene adsorption than MgF-embedded PLA and PVA films. Furthermore, a bio-efficacy study confirmed that MgF-embedded LDPE film could effectively delay banana ripening and extended their shelf life. In conclusion, this study indicates that MgF has promising potential as an ethylene adsorber for shelf life extension of bananas and probably other fresh produce.

Synthesis and CO2 adsorption kinetics of Aluminum Fumarate MOFs pellet with high recovery

As a promising CO2 adsorbent, Aluminum Fumarate (AlFu) metal organic frameworks (MOFs) were explored for pelletizing technology and CO2 adsorption characteristics. The effects of binder type (sodium carboxymethylcellulose (CMC), aluminum sol (AS)) and content (2.5 wt%-20 wt%), CO2 partial pressure (0.3 bar–1 bar) and temperature (35 °C–65 °C) on the mechanical performance and adsorption process were investigated. The results revealed that with the increase of binder mass, the pellet mechanical strength rose while the CO2 adsorption amount decreased. The AlFu pellet with 2.5 wt% CMC could retain the powder porosity and adsorption capacity. The mechanical strength of AlFu@CMC-2.5 wt% achieved 1.486 MPa, and the maximum adsorption capacity was 1.26 mmol/g at 35 °C and 1.0 bar. The CO2 adsorption capacity was increased with lower adsorption temperature and higher CO2 partial pressure. Compared with pseudo second order model and pseudo first order kinetic model, Avrami kinetic model could better describe the CO2 adsorption behavior of AlFu pellet. It indicated that the adsorption process was not a single physical or chemical adsorption. The rate-limiting kinetic analysis showed that the CO2 adsorption rate was determined by film diffusion and intraparticle diffusion rather than inter-particle diffusion.