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We conducted measurements of hydrogen adsorption on three coal samples of varying ranks at high pressure (0 to 102 bar) and elevated temperatures (303 K to 333 K) to assess their hydrogen storage potential. The excess adsorption capacity increased with increasing pressure but decreased with increasing temperature irrespective of coal rank. The highest hydrogen adsorption recorded was 0.721 mol/kg for the anthracite coal at 303 K and 102 bar. Furthermore, the hydrogen adsorption capacity correlated positively with coal vitrinite and fixed carbon contents (i.e. the high-rank coal exhibited greater adsorption), while all samples depicted predominantly type-I adsorption behavior for the entire pressure range. Micropore analysis and Fourier-transform infrared spectroscopy measurements were conducted to explore the microstructural and surface chemistry associated with these adsorption trends. The micropore content of the three samples followed the order: anthracite sub-bituminous bituminous, while H

Hypothesis Hydrogen geo-storage is considered as an option for large scale hydrogen storage in a full-scale hydrogen economy. Among different types of subsurface formations, coal seams look to be one of the best suitable options as coal’s micro/nano pore structure can adsorb a huge amount of gas (e.g. hydrogen) which can be withdrawn again once needed. However, literature lacks fundamental data regarding H2 diffusion in coal. Experiments In this study, we measured H2 adsorption rate in an Australian anthracite coal sample at isothermal conditions for four different temperatures (20°C, 30°C, 45°C and 60°C), at equilibrium pressure ∼13 bar, and calculated H2 diffusion coefficient ( D H 2 ) at each temperature. CO2 adsorption rates were measured for the same sample at similar temperatures and equilibrium pressure for comparison. Findings Results show that H2 adsorption rate, and consequently D H 2 , increases by temperature. D H 2 values are one order of magnitude larger than the equivalent D C O 2 values for the whole studied temperature range 20-60 °C. D H 2 / D C O 2 also shows an increasing trend versus temperature. CO2 adsorption capacity at equilibrium pressure is about 5 times higher than that of H2 in all studied temperatures. Both H2 and CO2 adsorption capacities, at equilibrium pressure, slightly decrease as temperature rises.

Metal organic frameworks (MOFs) are frequently used as adsorbents in adsorption processes to remove dyes from effluent produced by the textile industry. Today, dye contaminants have become an important environmental problem. One of these dyes is methylene blue (MB) and its removal from wastewater is a priority because it is persistent and nondegradable. MB is used in many industries although it has potential harmful effects on human and aquatic life and can be considered a hazardous chemical when in wastewater. The present study shows the potential applications for enhanced forms of UiO-66 MOFs, such as UiO-66, UiO-66-10%Al and UiO-66-30%Al. These forms were prepared to remove MB from wastewater using batch experiments. Characterisation of adsorbents were accomplished successfully using Fourier transform infrared, X-ray powder diffraction, Brunauer–Emmett–Teller surface area and thermogravimetric analysis techniques. To investigate equilibrium adsorptive behaviour, Langmuir and Freundlich isotherm models were tested against the experimental data. Based on linear regression correlation coefficient (R2), the Freundlich model described the equilibrium isotherm of MOF/MB better than the Langmuir model. Of all forms of UiO-66 MOF, UiO-66-10%Al had the maximum Langmuir adsorption capacity at 49.26 mg/g. A kinetics study examined pseudo first-order, pseudo second order and Elovich models to determine which could explain the sorption mechanism. While the pseudo second order and Elovich models showed a good fit with the experimental data, the correlation coefficient of the pseudo second-order model was the highest. These results indicate that adsorption of MB is controlled by a chemisorption mechanism. Further, intraparticle diffusion was utilised to describe the adsorption mechanism and determine the rate-limiting steps in the adsorption process.

In this study, three improved versions of UiO-66 metal organic frameworks (MOFs) were synthesised successfully: Different ratios of Ca+2/Zr+4 were used to synthesise UiO-66, UiO-66-10%Ca and UiO-66-30%Ca. Batch adsorption experiments were achieved to remove MB from wastewater by UiO-66-Ca. UiO-66-10%Ca exhibited the highest adsorption capacity with maximum MB adsorption capacity of 15 mg. g–1 in UiO-66-30%Ca while UiO-66 demonstrated lower MB loading. Langmuir and Freundlich models have been employed to describe isotherms. A kinetics study indicated pseudo first-order and pseudo second-order equations. In addition, an intraparticle diffusion model was utilised. The results presented here may facilitate the further enhancement of UiO-66 MOFs and advance the synthesis of multimetal MOFs in future research.

The LaMnO3 perovskite catalyst was successfully synthesized using a simple solid-state reaction method. This catalyst is used to activate PMS in the organic content's degradation process in the secondary effluent palm oil mill (POMSE). The organic content in POMSE is equivalent to the COD value; thus the COD value is used as a parameter for the process's success. The catalyst performance test shows that the catalyst effectively reduces COD, and the waste meets the maximum threshold allowed by government regulations. The variables that affect the catalyst's effectiveness were the calcination temperature of the catalyst, catalyst loading, PMS concentration, and temperature. The temperature of calcination affects the perovskite crystal formation; the higher the temperature, the more active catalyst obtained. The catalyst loading and PMS concentration variables affect the degradation process of organic levels in POMSE; at low levels, the higher the catalyst loading and PMS concentrations will increase the effectiveness of the degradation process, but at certain levels, the addition of catalysts and PMS reduces the effectiveness of the process. LaMnO3-800oC catalyst presents the highest activity of 92.7% and met the allowable threshold of COD < 300 mg/L. The sequence for removal of COD among the three catalysts with an order of LaMnO3-800oC > LaMnO3-700oC > LaMnO3-600 oC. The pseudo-second-order kinetics equation fits the experimental data. The effect of temperature on the kinetics constant follows the Arrhenius equation. Furthermore, the catalyst obtained was stable, with no significant decrease in catalysts activity up to three runs.

Dyes substances from the textile industry wastewater are internationally classified as poisonous substances, and they cause a severe threat to humans being and other living things, even at low concentrations. Therefore, this waste has to be treated before discharge to the environment. One of the most effective processes for degrading dyes is photocatalytic oxidation. Two different pretreatments of Spent bleaching earth (SBE) from palm oil refinery plant were applied to produce catalyst supports. The SBEe support was prepared by extraction using n-hexane, SBEc by calcination at 500 oC, and then used as a support for CeFeO3/SBEe and CeFeO3/SBEc perovskite catalyst. Both catalysts were tested for the degradation of methylene blue (MB) using photocatalytic oxidation. The properties of catalysts were characterized using some characterization methods, such as thermogravimetric-differential thermal analysis (TG-DTA), X-ray diffraction (XRD), scanning electron microscope (SEM) equipped with Dispersive Energy X-ray Spectroscopy (EDS), specific surface area (BET) and pore size analysis. CeFeO3/SBEe catalyst was found more efficient in photocatalytic oxidation for MB compared with the CeFeO3/SBEc catalyst. CeFeO3/SBEe catalyst could degrade 99.5% of MB during 120 min, at the condition of 25 mg/L MB, 1.0 g/L catalyst, and pH 7. The effect of pH on the performance of the catalyst followed the order of pH 7 > pH 9 > pH 5. Moreover, the CeFeO3/SBEe catalyst demonstrated excellent activity in the degradation of MB, displaying that CeFeO3/SBEe is a favorable catalyst for water purification.

In this study, two improved versions of UiO-66 were successfully synthesised. Modified UiO-66 and UiO-66-Ce were characterised to confirm the integrity of the structure, the stability of functional groups on the surface and the thermal stability. Activated samples were used for removal harmful anionic dye (methyl orange) (MO) from wastewater. Batch adsorption process was relied to investigate the competition between those MOFs for removing MO from aqueous solution. Based on the results, at a higher initial concentration, the maximum MO uptake was achieved by UiO-66-Ce which was better than modified-UiO-66. They adsorbed 71.5 and 62.5 mg g-1 respectively. Langmuir and Freundlich isotherms were employed to simulate the experimental data. In addition, Pseudo first order and Pseudo second order equations were used to describe the dynamic behaviour of MO through the adsorption process. The high adsorption capacities on these adsorbents can make them promised adsorbents in industrial areas.

Aluminum trimesate-based MOF (MIL-96-(Al)) has attracted intense attention due to its high chemical stability and strong CO2 adsorption capacity. In this study, CO2 capture and selectivity of MIL-96-Al was further improved by the coordination of the second metal Ca. To this end, a series of MIL-96(Al)–Ca were hydrothermally synthesised by a one-pot method, varying the molar ratio of Ca2+/Al3+. It is shown that the variation of Ca2+/Al3+ ratio results in significant changes in crystal shape and size. The shape varies from the hexagonal rods capped in the ends by a hexagonal pyramid in MIL-96(Al) without Ca to the thin hexagonal disks in MIL-96(Al)–Ca4 (the highest Ca content). Adsorption studies reveal that the CO2 adsorption on MIL-96(Al)–Ca1 and MIL-96(Al)–Ca2 at pressures up to 950 kPa is vastly improved due to the enhanced pore volumes compared to MIL-96(Al). The CO2 uptake on these materials measured in the above sequence is 10.22, 9.38 and 8.09 mmol g−1, respectively. However, the CO2 uptake reduces to 5.26 mmol g−1 on MIL-96(Al)–Ca4. Compared with MIL-96(Al)–Ca1, the N2 adsorption in MIL-96(Al)–Ca4 is significantly reduced by 90% at similar operational conditions. At 100 and 28.8 kPa, the selectivity of MIL-96(Al)–Ca4 to CO2/N2 reaches up to 67 and 841.42, respectively, which is equivalent to 5 and 26 times the selectivity of MIL-96(Al). The present findings highlight that MIL-96(Al) with second metal Ca coordination is a potential candidate as an alternative CO2 adsorbent for practical applications.

Wettability is one of the main parameters controlling CO2 injectivity and the movement of CO2 plume during geological CO2 sequestration. Despite significant research efforts, there is still a high uncertainty associated with the wettability of CO2/brine/rock systems and how they evolve with CO2 exposure. This study, therefore, aims to measure the contact angle of sandstone samples with varying clay content before and after laboratory core flooding at different reservoir pressures, of 10 MPa and 15 MPa, and a temperature of 323 K. The samples’ microstructural changes are also assessed to investigate any potential alteration in the samples’ structure due to carbonated water exposure. The results show that the advancing and receding contact angles increased with the increasing pressure for both the Berea and Bandera Gray samples. Moreover, the results indicate that Bandera Gray sandstone has a higher contact angle. The sandstones also turn slightly more hydrophobic after core flooding, indicating that the sandstones become more CO2-wet after CO2 injection. These results suggest that CO2 flooding leads to an increase in the CO2-wettability of sandstone, and thus an increase in vertical CO2 plume migration and solubility trapping, and a reduction in the residual trapping capacity, especially when extrapolated to more prolonged field-scale injection and exposure times.

Aluminum trimesate-based MOF (MIL-96-(Al)) has attracted intense attention due to its high chemical stability and strong CO

Mono-ethylene glycol (MEG), used in the oil and gas industries as a gas hydrate inhibitor, is a hazardous chemical present in wastewater from those processes. Metal-organic frameworks (MOFs) (modified UiO-66∗ and UiO-66-2OH) were used for the effective removal of MEG waste from effluents of distillation columns (MEG recovery units). Batch contact adsorption method was used to study the adsorption behavior toward these types of MOFs. Adsorption experiments showed that these MOFs had very high affinity toward MEG. Significant adsorption capacity was demonstrated on UiO-66-2OH and modified UiO-66 at 1000 mg·g−1 and 800 mg·g−1 respectively. The adsorption kinetics were fitted to a pseudo first-order model. UiO-66-2OH showed a higher adsorption capacity due to the presence of hydroxyl groups in its structure. A Langmuir model gave the best fitting for isotherm of experimental data at pH = 7.

In this paper, we demonstrate a cascade application of functional materials in adsorption and catalysis. Metal organic frameworks, MIL-96, were synthesized by a single solvent (water), and methanol (MIL-96-Me) or ethanol (MIL-96-Et) modulated method. Methanol modulation results in a change in porous structure and better CO2 adsorption and selectivity. After gas-phase adsorption of CO2, the MIL-96 can be reused for liquid-phase removal of water contaminants, demonstrating high capacities of para-hydroxybenzoic acid (p-HBA). Then, a transformation of the used MIL-96 by pyrolysis was employed to produce a metal oxide/C composite for catalytic activation of peroxymonosulfate (PMS) to degrade an organic pollutant, methyl orange. The composite exhibited excellent performance in the dye degradation. This study presents a proof of concept of integrated utilization of robust and functional nanomaterials for multiple applications without producing solid wastes after each use.

This study was undertaken to evaluate the effects of mixing BDC-NO2 and BDC-NH2 linkers in the synthesis of Zr-based metal organic frameworks (Zr-MOFs) on their adsorption and separation of CO2 and CH4. UiO-66 with single or binary -NO2 and -NH2 samples were synthesized under solvothermal conditions and activated by solvent exchanging using methanol. Structural analyses of the materials were conducted using FTIR, XRD, TGA, SEM, 1HNMR and N2 adsorption/desorption techniques and adsorption of CO2 and CH4 at high pressures and different temperatures (273 and 298 K) was investigated. It was found that UiO-66-NH2 exhibited higher CO2 and CH4 adsorption capacities than those of UiO-66-NO2. Addition of -NH2 functional group in UiO-66-NO2 could enhance CO2 and CH4 adsorption due to the extra CO2 adsorption sites of -NH2 functional groups. Addition of -NO2 functional group to UiO-66-NH2 at a low loading could also increase CO2 and CH4 adsorption, however, a high loading of NO2 functional group to UiO-66-NH2 would result in decreased adsorption. Keywords: UiO-66–NO2, UiO-66-NH2, Multi-linker MOFs, Carbon dioxide, Methane adsorption

The affinity of the basalt surfaces towards CO2, quantified as wettability functions, is one of the most important driving factors for CO2 trapping capacity and containment security. SiO2 is a minor constituent, often found in traces in the seawater and formation brine injected or reinjected into the sub-surface formations. This work, thus, evaluates the effect of nano-sized SiO2 (100, 1000, and 2000 mg. L−1) on the wettability of the basalt rock surface in the pressure range of 5-20 MPa. The results from brine/CO2/rock wettability measurements show that SiO2 nanoparticles turn the CO2-wet basalt surface to weakly water-wet upon aging with nanofluids. About 40% reduction in the measured brine contact angle takes place upon treatment of the rock sample with 1000 mg. L−1 nanoparticles. We hypothesize that this change in wettability may facilitate enhanced capillary or residual trapping of CO2 in the basalt formation having adequate porosity and permeability to enhance the basalt CO2 trapping capacity.

Amino-MIL-53(Al) was solvothermally synthesized using co-solvents, such as methanol (M), ethanol (E), methanol/acetic acid (MA), or ethanol/acetic acid (EA), as modulators with dimethylformamide (D). The effects of co-solvents on physicochemical properties of amino-MIL-53(Al) were investigated. It was found that the addition of co-solvents in the synthesis leads to the reduction of crystallinity and crystal size of the samples. The textural properties, such as specific surface area and porous structure, were manipulated. Amino-MIL-53-DMA exhibited the highest Brunauer–Emmett–Teller surface area of 632 m2/g as a result of the loss of the bridging hydroxyl group, while amino-MIL-53, amino-MIL-53-DE, amino-MIL-53-DEA, and amino-MIL-53-DM presented the surface areas of 400, 356, 321, and 348 m2/g, respectively. However, the primary amine groups were maintained on the surface of all of the amino-MIL-53 samples. The co-solvents enhanced CO2 adsorption on modified amino-MIL-53. CO2 adsorption capacities on amino...

Climate change is a key problem of the 21st century. Climate change is mainly caused by anthropogenic CO2 emissions, and one solution to this problem is to capture and store CO2 in deep coal seams, where it is immobilized by adsorption to the coal surface. Here we propose to modify the coal with methyl orange (MO), a typical dye that is also a major pollutant of the hydrosphere and removed thereby. Thus, raw and MO-modified coals were characterized to investigate their thermal stabilities, textural properties, carbon contents, surface characteristics, and CO2 adsorption on the coal samples was measured at typical storage conditions (323 K and pressures up to 37.5 bar). CO2 adsorption dramatically increased in the MO-coal, from 1.95 mol. kg−1 (raw coal) to 18.7 mol. kg −1. This work thus aids in the development of improved methods for CO2 storage, to significantly mitigate climate change.

In this study, MIL-53, MIL-96, and amino-MIL-53 were prepared, characterized, and tested for CO2 adsorption. These metal-organic frameworks (MOFs) exhibit different characteristics, although MIL-53 and amino-MIL-53 have the same topology. The BET surface areas are 1519, 687, and 262 m2/g for MIL-53, MIL-96, and amino-MIL-53, respectively. They exhibit different thermal stability with MIL-53 having the highest stability which starts to decompose at 773 K, while amino-MIL-53 and MIL-96 show lower thermal stability, decomposing upon heating up to 650 and 570 K, respectively. Static adsorption of CO2 at 1 bar and 273 K was conducted, showing CO2 adsorption capacities of 64, 124, and 48 cc/g for MIL-53, MIL-96, and amino-MIL-53, respectively. The heat of adsorption for CO2 was found to be 39, 28.6, and 28 kJ/mol for MIL-53, MIL-96, and amino-MIL-53, respectively. Dynamic adsorption experiment shows that MIL-53 achieves the highest working capacity among all three materials around 169 cc/g at 1 bar and room temperature (304 K). Amino-MIL-53 shows a dynamic adsorption capacity of 121 cc/g at the same conditions and MIL-96 demonstrates a dynamic adsorption of 98.2 cc/g at 1 bar and 298 K. The higher working capacity demonstrated by MIL-53 and amino-MIL-53 are attributed to their larger pore size, making them promising candidate adsorbents for practicing carbon capture in real-world applications.

Muder Al Haydar,1,2 Hussein Rasool Abid,3,4 Bruce Sunderland,5 Shaobin Wang6 1Pharmaceutics Department, College of Pharmacy, University of Kerbala, Kerbala, Iraq; 2Pharmaceutics Department, School of Pharmacy, Faculty of Health Sciences, Curtin University, Perth, WA, Australia; 3Department of Chemical Engineering, Curtin University, Perth, WA, Australia; 4Environmental Health Department, College of Applied Medical Sciences, University of Kerbala, Kerbala, Iraq; 5School of Pharmacy, Faculty of Health Sciences, Curtin University, Perth, WA, Australia; 6Department of Chemical Engineering, School of Chemical and Petroleum Engineering, Faculty of Science and Engineering, Curtin University, Perth, WA, Australia Background: Multimetal organic frameworks (M-MOFs) were synthesized by including a second metal ion with the main base metal in the synthesis process to enhance their applications for drug delivery. Aceclofenac (ACF), a nonsteroidal anti-inflammatory analgesic drug of low aqueous solubility, was selected as a candidate for the drug delivery system Purpose: This study aimed to evaluate the loading capacity (LC) and entrapment efficiency (EE) percentages of multi-Material of Institute Lavoisier (MIL)-100(Fe) (M-MIL-100(Fe)) for ACF. Materials and methods: Hydrothermal synthesis procedure was used to prepare multi-MIL-100(Fe) samples (Zn I-MIL-100(Fe), Zn II-MIL-100(Fe), Ca I-MIL-100(Fe), Ca II-MIL-100(Fe), Mg I-MIL-100(Fe), Mg II-MIL-100(Fe), Mn I-MIL-100(Fe), and Mn II-MIL-100(Fe)). The characterization of M-MIL-100(Fe) samples was evaluated by X-ray powder diffraction (XRD), Fourier transform infrared spectra, scanning electron microscope (SEM), TGA, and N2 adsorption isotherms. The LC of M-MIL-100(Fe) and EE of ACF were determined. Nuclear magnetic resonance (NMR) and zeta-potential analyses were employed to confirm qualitatively the drug loading within M-MIL-100(Fe). Results: The ACF LC of MIL-100(Fe) was 27%, whereas the LC of M-MIL-100(Fe) was significantly increased and ranged from 37% in Ca I-MIL-100(Fe) to about 57% and 59% in Mn II-MIL-100(Fe) and Zn II-MIL-100(Fe), respectively. The ACF@M-MOFs release profiles showed slow release rates in phosphate buffer solutions at pH 6.8 and 7.4 as compared to the ACF@MIL-100(Fe). Conclusion: Therefore, M-MOFs showed a significant potential as a carrier for drug delivery systems. Keywords: aceclofenac, Mixed metal-MOF, MIL-100, drug delivery, drug loading