Direct Synthesis of Ethylene and Hydrogen from CO2 and Ethane over a Bifunctional Structured CaO/Cr2O3-V2O5/ZSM-5 Adsorbent/Catalyst Monolith

In this study, we synthesized bifunctional adsorbent/catalyst materials (BFMs) consisting of a CaO adsorbent admixed with Cr2O3-V2O5/ZSM-5 catalysts. The obtained BFMs were further formulated, processed, and shaped through additive manufacturing (3D printing) method. The physical and chemical properties of structured CaO/Cr2O3-V2O5/ZSM-5 adsorbent/catalyst monoliths were thoroughly characterized and evaluated. The effects of operating conditions including reaction temperature, ethane composition, and space velocity on single-bed CO2 capture and selective formation of ethylene and hydrogen were systematically investigated. The adsorption-reaction experiments revealed that Cr-based BFMs, in particular, CaO/Cr4/ZSM-5 monoliths undergo the oxidative dehydrogenation pathway with high C2H4 selectivity, whereas increasing the content of V leads to enhanced catalytic activity for the reforming pathway to produce hydrogen. The best adsorption/catalyst BFM performance was observed for CaO/Cr1-V3/ZSM-5, which was balanced between the two reaction pathways and resulted in 1.72 mmol/g CO2 capture capacity, 63.95% CO2 conversion, 22.4% C2H6 conversion, 42% C2H4 selectivity, and 45% syngas (31% hydrogen) selectivity. Furthermore, the cyclic test results revealed excellent catalytic stability across the initial two cycles over CaO/Cr1-V3/ZSM-5 monolith, highlighting the synergetic effect of bimetallic catalyst constituents on maintaining high catalytic durability. This novel formulation and processing method can pave the way toward formulation of various structured BFM monoliths with cooperative CO2 adsorptive removal and catalytic performance for one-pot CO2 capture-utilization and simultaneous production of light olefins and hydrogen

Process to Produce High Surface Area Nanoparticle Vanadium Phosphorus Oxide Catalyst and Product Derives Thereof

An improved process to produce high surface area nanoparticle vanadium phosphorus oxide catalysts comprises the steps of reducing vanadium-containing compounds in an alcohol solution selected from the group consisting of isobutanol and benzyl alcohol and any combination derives thereof under reflux for 4 to 6 hours to form a suspended mixture; reacting dopants and phosphorus-containing compounds to the suspended mixture under reflux for 30 minutes to 3 hours to form precursors of the vanadium phosphorus oxide catalysts; drying the formed precursors; and calcining the dried precursors in a flow of gaseous n-butane/air mixture at 400 to 460° C. to form activated vanadium phosphorus oxide catalysts

Zeolitic 3D Scaffolds with Tailored Surface Topography for Methanol Conversion with Light Olefins Selectivity

The present disclosure relates to 3D printed zeolite scaffolds . The zeolite scaffolds can be used as a catalyst for methanol to olefin ( MTO ) conversion and hydrocarbon cracking processes

Magnetic-Induced Swing Adsorption Over Iron Oxide/13X: Effects Of Particle Size And Oxide Phase On Sorbent Regeneration In Ethylene/Ethane Separation

Magnetic induction has emerged as a viable method for regeneration of sorbents during separation processes. In this work, we investigated the efficacy of magnetic sorbents comprising iron oxide and zeolite 13X in ethylene/ethane separation via a magnetic induction process. The electromagnetic properties of the sorbents were tuned by varying the iron oxide (Fe2O3) particle size (30 nm, 100 nm, 5 μm) and iron oxide phase structure (FeO, Fe2O3, Fe3O4) at 20 wt % loading. The effects of these parameters on adsorption capacity, selectivity, and desorption rates were systematically investigated. The microporosity and surface area of magnetic sorbents were reduced by increasing the particle size of Fe2O3 from 30 nm to 5 μm. The results indicated that regardless of iron oxide particle size or phase structure, the C2H4/C2H6selectivity ranges between 2.44 and 2.65 for all the magnetic sorbents. The specific heat absorption rate (SAR) was increased by ∼60% upon increasing the magnetic field intensity from 21.4 to 31.4 mT when the particle size increased from 30 nm to 5 μm. Fe3O4 was found to outperform the other phases by exhibiting 91.3 and 93.3% higher SAR than Fe2O3and FeO at 31.4 mT, respectively, owing to its unique lattice structure with dual ion states (Fe2+and Fe3+). Fe3O4/13X exhibited an ethylene desorption rate of 0.41 mmol/g·min at 21.4 mT, which was 58.5% faster than that under conventional thermal heating. Additionally, the sorbent was found to be highly durable, maintaining its adsorption and desorption capabilities over five consecutive cycles in the magnetic induction swing adsorption (MISA) process, conducted at 25 °C and 1 bar during adsorption and at 31.4 mT during desorption. These results indicate the potential of Fe3O4/13X as an effective magnetic sorbent in the MISA process. This study builds on our previous proof-of-concept work on the potential of magnetic sorbents as stimuli-responsive materials for light olefin/paraffin separation

Development and Assessment of Magnetic Fe2O3@MOF-74 Composite Sorbents for Ethylene/ethane Separation

Development of smart sorbents that can be regenerated when triggered by external stimuli such as magnetic field can overcome the poor energy utilization of the current sorbents investigated for light olefins/paraffins separation. In this work, we report the development of novel magnetic sorbents comprising of MOF-74 crystals and superparamagnetic Fe2O3 particles in a core–shell structure, and assessment of their C2H4/C2H6 separation performance. The electromagnetic properties of the materials were tuned by varying the Fe2O3 (Fex) loading (x = 1–20 wt%), and their effects on adsorption capacity, selectivity, and desorption rates were systematically investigated. The surface area, microporosity, and the C2H4/C2H6 selectivity of composites were reduced as the Fex content increased, while the specific heat absorption rate (SAR) was increased from 60 to 80 % upon varying the magnetic field intensity from 12.6 to 31.4 mT. On the basis of the SAR enhancement upon increasing the Fex loading, the C2H4 desorption rates were gradually increased with Fex up to 10 wt%, however beyond this composition a decline in the desorption rates was noted. Moreover, the cooling rate was found to be ∼76 % higher in induction heating compared to the conventional thermal heating method, which is expected to significantly shorten the cycle time, thereby reducing the column size and improving the throughput of the system. Our results highlight the importance of assessing the trade-offs between capture capacity and extent of responsiveness to magnetic field (i.e., temperature rise during regeneration) when developing smart sorbents. This work builds on previous studies that demonstrate the suitability of novel stimuli-responsive sorbents for next generation of olefin/paraffin separation systems

System, Devices and Methods for Molecular Separation

Systems, devices and methods for molecular separation including a molecular separation device comprising at least a polycrystalline metal-organic framework (MOF) and a nanocrystalline, zeolite MFI, wherein the MOF forms a polycrystalline membrane with zeolite MFI nanoparticles dispersed therein, and the MOF membrane matrix contacting and surrounding the zeolite MFI nanoparticles form a permselective nanoporous structure

Kinetic Assessment Of Light Hydrocarbons Separation Over Fe-Doped 13X Composite Sorbents Under Multicomponent Feed Conditions

Current sorbents investigated for light olefin/paraffin separation usually suffer from low selectivity. Besides, multicomponent analysis of this important separation is usually overlooked in the literature. To enhance the separation efficiency of zeolite 13X, we developed a series of Fe2O3/13X composite sorbents and assessed their separation performance using binary, ternary, and multicomponent gas mixtures of C2H4, C2H6, CH4, and H2. In these composites, nano- and micro Fe2O3 particles (NPs and MPs) with varied loadings were used, while Fe was also ion-exchanged into the 13X zeolite structure. The microporosity and surface area of the bare sorbent were reduced upon increasing Fex loading for all particle sizes. However, Fe1(NPs)/13X demonstrated a higher C2H4 adsorption capacity and C2H4/C2H6 selectivity despite its lower surface area, which was attributed to its higher surface electron transfer property that enhanced its adsorption performance via electrostatic interactions. Additionally, the incorporation of Fe1 into the 13X framework resulted in narrowing of the micropore channels, thereby promoting the molecular sieving effect and improving the selectivity toward C2H4. The dynamic adsorption results revealed the reduction in C2H4/(C2H6 + CH4 + H2) selectivity in the presence of impurity gases (CH4 and H2), from 4.10 to 3.84 and 3.20 for binary, ternary, and multicomponent gas mixtures, respectively. Nevertheless, the C2H4/C2H6 selectivity was found to be roughly constant at ∼4 across all feed conditions. Moreover, the affinity of Fe1(NPs)/13X toward different adsorbates from the most adsorbed to the least adsorbed component was in the order of C2H4 \u3e C2H6 \u3e CH4 \u3e H2, while the rates of species transport were found to be primarily dependent on the rates of molecular diffusion within the pores of the 13X zeolite

Formulation and Processing of Dual Functional Adsorbent/Catalyst Structured Monoliths using an Additively Manufactured Contactor for Direct Capture/Conversion of CO2 with Cogeneration of Ethylene

Utilizing CO2 as a mild oxidant for oxidative dehydrogenation of ethane (ODHE) is an attractive way of recycling this greenhouse contaminant. Typically, CO2 capture and conversion processes are performed in separate beds, however, combining these processes into one bed incurs advantages of lower thermal gradient and reduced energy costs. This study formulated the first generation of structured dual-functional materials (DFMs) by directly 3D printing metal-oxide-CaO/ZSM-5 inks into monolithic contactors. Specifically, we 3D-printed monoliths with V, Ga, Ni, or Ti dopants to perform metal screening and determine which metal generates the best structured DFM for combined CO2 capture and utilization in ODHE. The samples were vigorously characterized by X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), N2 physisorption, NH3-temperature programmed desorption (NH3-TPD), H2-temperature programmed reduction (H2-TPR), energy dispersive spectroscopy (EDS), and Pyridine Fourier Transform Infrared Spectroscopy (Py-FTIR). Their CO2 capture/ODHE performances were assessed with CO2 adsorption at 600 °C and ODHE of 25 mL/min 7% C2H6 at 700 °C. The combined adsorption/catalysis experiments indicated that the best performance was observed in V-CaO/ZSM-5 which achieved a staggeringly high CO2 capture (5.4 mmol/g), 65.2% CO2 conversion, 36.5% C2H6 conversion, 98% C2H4 selectivity, and 35.8% C2H4 yield as well as zero thermal cracking after 40 min-on-stream. This performance exceeded that of any previously reported material for combined CO2 capture and ODHE utilization, indicating this novel printing method can generate DFMs with exceptional potential for combined CO2 capture and utilization processes

High Efficiency, High Performance Metal-Organic Framework (MOF) Membranes in Hollow Fibers and Tubular Modules

A reactor cell for measuring gas and liquid permeation is disclosed. A hollow fiber is supported by and sealed into a first hole and a second hole of the reactor module. The first and second ends of the hollow fiber are sealed with a sealing solution. Methods for making and using the reactor cell are also disclosed. As made and used, the reactor cell further comprises a molecular sieving membrane that is uniform and free of defects grown on an inner bore surface of the hollow fiber

Drug Delivery On Mg-MOF-74: The Effect Of Drug Solubility On Pharmacokinetics

Biocompatible metal-organic frameworks (MOFs) have emerged as potential nanocarriers for drug delivery applications owing to their tunable physiochemical properties. Specifically, Mg-MOF-74 with soluble metal centers has been shown to promote rapid pharmacokinetics for some drugs. In this work, we studied how the solubility of drug impacts the pharmacokinetic release rate and delivery efficiency by impregnating various amounts of ibuprofen, 5-fluorouracil, and curcumin onto Mg-MOF-74. The characterization of the drug-loaded samples via X-ray diffraction (XRD), N2 physisorption, and Fourier transform infrared (FTIR) confirmed the successful encapsulation of 30, 50, and 80 wt % of the three drugs within the MOF structure. Assessment of the drug delivery performances of the MOF under its various loadings via HPLC tests revealed that the release rate is a direct function of drug solubility and molecular size. Of the three drugs considered under fixed loading condition, the 5-fluorouracil-loaded MOF samples exhibited the highest release rate constants which was attributed to the highest degree of solubility and smallest molecular size of 5-fluorouracil relative to ibuprofen and curcumin. It was also noted that the release kinetics decreases with drug loading, due to a pharmacokinetic shift in release mechanism from singular to binary modes of compound diffusion. The findings of this study highlight the effects of drug\u27s physical and chemical properties on the pharmacokinetic rates from MOF nanocarriers