eSTOMP Open Source
The eSTOMP-WR mode is designed to efficiently simulate isothermal variably saturated flow (Richards Equation) and multicomponent reactions in porous media on the most powerful computers available.
Nanomaterials for Sodium-Ion Batteries
We prepared single, crystalline, Na4Mn9O18 nanowires with a polymer-pyrolysis method using polyacrylates of Na and Mn as precursor compounds. The optimized Na4Mn9O18 materials display high crystallinity and a homogeneous nanowire structure, which provides a mechanically stable structure as well as a short diffusion path for Na-ion intercalation and extraction. The Na4Mn9O18 nanowires have shown a high reversible capacity (128 mA h g-1 at 0.1C), excellent cycleability (77% capacity retention for 1000 cycles at 0.5C), and promising rate capability for Na-ion battery applications. The outstanding performance of the Na4Mn9O18 nanowires makes them a promising candidate to construct a viable and low-cost Na-ion battery system for upcoming power and energy storage systems.
A METHOD TO CONTROL THE ETCHING RATE OF MATERIALS
The invention discloses a method to control the etching rate and safety of materials, including but not limited to etching of silicon (Si) based materials. An etchant system that can etch silicon oxides (SiOx) but does not oxidize Si has been developed to effectively remove SiOx while keeping Si largely intact. The etchant system uses organic solvents as one of the additional components in etching medium. The organic solvents have the following properties: 1) they are not miscible with water and 2) etching agents can dissolve in such solvents. The candidates of organic solvents include but are not limited to aromatic compounds such as benzene, toluene, xylene, cumene, etc. and aliphatic compounds such as hexane, cyclohexane, pentane, decene, etc and a mixture of such solvents. Compared to conventional aqueous based etchants, this method leads to mild reaction with low heat generation rate and avoids the safety hazard associated with bubbling/spilling occurred in the conventional etching methods. It also increased etching yield of porous Si (Psi) by preventing over-etching of Si. In addition, the etching agent used in this etchant system is easy to be separated and recycles/reused so the total cost of etching process is largely reduced.
SYSTEMS AND METHODS FOR PREPARING BUTENES
This invention relates to the single step conversion of ethanol and/ or aldehydes (i.e. acetaldehyde, butyraldehydes, crotonaldehyde) (either aqueous or neat) to 1- and 2-butenes-rich olefins. 1-Butene itself a commodity chemical can be converted into polybutene, its main application is as a comonomer in the production of certain kinds of polyethylene, such as linear low-density polyethylene (LLDPE). 1-Butene has also been used as a precursor to polypropylene resins, butylene oxide, and butanone. Mixtures of 1-butene and 2-butene, as produced by the methods disclosed in this invention, can be oligomerized and hydrogenated into gasoline, jet, and diesel fuels and/or into valuable fuel additives and lubricants. For the current alcohol-to-jet process, producing 1- and 2-butene from ethanol is performed in two separate steps by first dehydrating ethanol into ethylene and then dimerizing e thylene into 1- and 2-butene in a second step. Here we disclose the methods for producing 1- and 2-butene mixtures directly from either ethanol, acetaldehyde, butyraldehyde, corotonaldehyde or mixture of ethanol with one of these aldehydes. This is done using specially tailored polyfunctional catalysts comprising metal component with relatively weak hydrogenation ability (e.g., Cu) with mildly acidic support materials (e.g., ZrO2 supported on SiO2). In previous work, including a separate patent, we demonstrated such catalytic materials to be active for converting ethanol into 1,3-butadiene in one reactor. In a separate patent, we demonstrated supported Ag catalysts to be active for (aqueous) ethanol conversion into a mixture of 1 and 2-butenes. Direct conversion of aldehydes or mixture of aldehydes and ethanol into 1 and 2-butenes rich olefins has not been reported before. In this disclosure, we report these catalysts to be active and selective for converting ethanol and/ or aldehydes to 1- and 2-butenes in one single reactor under mild reducing conditions (e.g., under H2, T = 400 degrees C, P = 7 bar). Furthermore, catalyst formulation (i.e. effect of the nature of the support, promoters addition, Cu loading and ZrO2 loading) and process parameters such as H2 concentration, ethanol partial pressure, space velocity were demonstrated to have significant effect on conversion, selectivity, and stability. Results are shown in separate word document with experimental data included in Tables and Figures Here we also demonstrate how catalytic stability is enhanced for the Cu-based catalyst as compared to the Ag-based catalyst. The Cu-based catalyst presents higher resistance to coking and oxidation which enables superior durability. The product from the ethanol and or aldehyde(s) conversion contains primarily butenes and ethylene olefins mixed with H2. We previously demonstrated in a separate patent how these butenes-rich olefins can be oligomerized into gasoline, jet, diesel range hydrocarbons.
HIGH-THROUGHPUT ELECTROCHEMICAL CHARACTERIZATION APPARATUS AND SYSTEM AND METHODS FOR USING THE SAME (iEdison No. 0685901-23-0011)
The invention relates to a design of a high-throughput (HPT) electrochemical characterization system (can be used as electrochemical screening platforms or multi-channel reactors) and its applications in redox flow batteries or other energy storage and conversion systems. The HTP electrochemical characterization system includes an array of holes for holding liquid samples (a), a bottom electrode part for counter electrode function (b), a top electrode part for working electrode and reference electrode function (c), a top electrode holder part for grouping the electrodes and integrating with robotic arm (d), and a bottom electrode holder part for size matching with deck layouts of the commercial available robotic platforms (such as the size of microtiter plates) and heating or cooling function (e).
Planar High Density Sodium Battery
A method of making a molten sodium battery is disclosed. A first metallic interconnect frame having a first interconnect vent hole is provided. A second metallic interconnect frame having a second interconnect vent hole is also provided. An electrolyte plate having a cathode vent hole and an anode vent hole is interposed between the metallic interconnect frames. The metallic interconnect frames and the electrolyte plate are sealed thereby forming gaseous communication between an anode chamber through the anode vent hole and gaseous communication between a cathode chamber through the cathode vent hole.
GRAPHENE-SULFUR NANOCOMPOSITES FOR RECHARGEABLE LITHIUM-SULFUR BATTERY ELECTRODES
Rechargeable lithium-sulfur batteries having a cathode that includes a graphene-sulfur nanocomposite can exhibit improved characteristics. The graphene-sulfur nanocomposite can be characterized by graphene sheets with particles of sulfur adsorbed to the graphene sheets. The sulfur particles have an average diameter less than 50 nm.
PROCESSES FOR THE CONVERSION OF MIXED OXYGENATES FEEDSTOCKS TO HYDROCARBON FUELS
Methods, systems and catalysts for converting an alcohol containing feedstock to an upgraded material in a single catalyst bed wherein a feedstock is fed to a catalyst under preselected conditions to obtain an intermediate; and condensing the intermediate through an aldol condensation reaction to yield a product containing an upgraded material. In one instance the feedstock includes ethanol, the catalyst is a mixed metal oxide catalyst and the upgraded material is typically a C.sub.5+ ketone(s) or alcohol(s), such as 2-pentanone, 2-heptanone, 4-heptanone and 2-nonanone.
SUBSTRATE MODIFICATION WITH CROSSLINKED BRANCHED POLYMER FOR USE IN BATTERIES (iEdison No. (iEdison No. 0685901-19-0015))
A new modification of graphitic carbon felt (GCF) as an electrode for all-vanadium redox flow batteries (VRBs) was developed with cross-linked polymer film which helps to improve long-term cycling ability of the cells. The polymer modification which causes the vanadium coordination effect with tertiary amine groups of the main chains avoids the severe oxidation and preserves the concentration of vanadium species during long-term redox cycling. Besides the ability of polymer films keeps the membrane surface clean without precipitation of vanadium compounds [e.g. vanadium (V) sulfate, V2(SO4)5 or vanadium (IV) oxide sulfate, VOSO4] arising at high SOC which causes increasing temperature due to the electrostatic attraction between the ionized amine groups and SO42- ions. This is a good way to keep the internal resistance stable. The schematic illustrations of typical VRB system and with polyethyleneimine cross-linked with glutaraldehyde (PG) modified GCF electrodes are shown in Fig. 1. The PG modified GCF electrode was fabricated via stamping method with PEI (5 Wt.%, branched) and GA (1Wt.%) solutions. One-fifth of pristine GCF electrode (5*6 cm2) is immersed in each solution one by one two times. Then it is dried at 70ºC in vacuum for 5 hours and washed with de-ionized (DI) water several times. The PEIGA modified GCF (PGGCF) electrode dried overnight are used as positive and negative electrodes. This modification method has been proposed or demonstrated as proof of concepts for the new interphase between membrane and carbon electrode. Fig. 2 shows SEM images of (a, b and c) pristine GCF and (d, e and f) PGGCF electrodes with different magnifications. After PG coating, the string surface of PGGCF electrode became smooth with very thin polymer films like a spider web formed between carbon strings. Thus, the coating method is efficient way to get thin PG films on each string and between them. Based on SEM-EDX analysis, the polymer films are consisting of carbon, oxygen and nitrogen, as shown in Fig. 3. FT-IR spectrum of PGGCF electrode shows typical N-H and C-N stretching vibrations corresponding to PEI while the pristine GCF does not show them meaning that PEI was successfully coated on GCF electrode, as shown in Fig.4. The chemical reaction to form the PEIGA is shown in Fig. 5. The electrochemical performance of PGGCF and pristine GCF electrodes was evaluated in vanadium 3+ and 4+ solutions as negative and positive electrolytes (1.5M VOSO4 with 3.5M H2SO4), respectively with N115 membrane. The flow rate of electrolytes was 30ml/min and current was 50mA/cm2 operated in cut-off voltage range of 0.8-1.6V. As shown in Fig. 6, cycling stability of PGGCF cell with high cycling Coulombic efficiency (CE) is much better than GCF baseline cell for 100 cycles although the energy efficiency (EE) of PGGCF cell is lower than baseline cell due to their lower electrical conductivity and smaller surface area caused by polymer coating than pristine electrode. Fig. 7 shows the charge-discharge curves of the GCF baseline and PGGCF cells at 1st, 50th and 100th. The capacity decrease of baseline cell is observed in Fig. 6a with increasing overpotential and decreasing charge-discharge time as cycling proceeded, as shown in Fig. 7a while cycling ability of PGGCF cell is much more stable without severe increasing cell polarization. The poor cycling stability of baseline cell could be attributed to the concentration polarization of active species as cycling proceeded. Basically the concentration polarization results from vanadium crossover over prolonged cycling, but we found out different reason in this study. Based on ICP analysis for the electrolytes after 100 cycles, the oxidation of vanadium 4+ especially in positive electrolyte is considered as the main reason why the baseline has the concentration polarization. As a result, the amount of redox-active species (V4+) in positive side was significantly reduced and it becomes irreversible, as shown in Fig. 1a. Another reason we found is the precipitation of vanadium compounds on the membrane which may cause the decreasing proton conductivity and further increasing cell polarization. On the other hand, the concentration of V4+ in positive electrolyte of PGGCF cell after 100 cycles is almost same as the beginning of cell test meaning that PG modification helped to stabilize the oxidation state of V4+ for 100 cycles due to the vanadium coordination effect of PEI, as shown in Fig. 1b. To verify it, the cycled electrodes were analyzed by SEM-EDX showing that vanadium and sulfur atoms were detected in the polymer phase coated on the strings. A lot of tertiary amine groups on PEI backbone and their branches and ionized amine groups in the acidic electrolytes can coordinate vanadium and sulfur ions during the prolonged cycling. The effect of PG modification on membrane is shown in Fig. 9 showing digital photographs and SEM images of Nafion 115 membranes in the GCF baseline and PGGCF cells after 100 cycles. Theoretically the vanadium compounds are formed in vanadium electrolytes with different oxidation states [(a) 3+, (b) 4+ and (c) 5+] at high temperature (50ºC, stored for 2 weeks), as shown in Fig. 10. Therefore it is likely that vanadium compounds form at high SOC which causes increasing temperature in the cell especially during long-term cycling. In case of GCF baseline cell, the cycled membrane has lots of precipitates on the membrane surface while that of PGGCF cell has a clean surface without precipitates meaning that PG modification helps to avoid the precipitation which causes loosing redox-active species and increasing cell polarization as cycling proceeded.
Hydroxymethylfurfural Reduction Methods and Methods of Producing Furandimethanol
A method of reducing hydroxymethylfurfural (HMF) where a starting material containing HMF in a solvent comprising water is provided. H2 is provided into the reactor and the starting material is contacted with a catalyst containing at least one metal selected from Ni, Co, Cu, Pd, Pt, Ru, Ir, Re and Rh, at a temperature of less than or equal to 250° C. A method of hydrogenating HMF includes providing an aqueous solution containing HMF and fructose. H2 and a hydrogenation catalyst are provided. The HMF is selectively hydrogenated relative to the fructose at a temperature at or above 30° C. A method of producing tetrahydrofuran dimethanol (THFDM) includes providing a continuous flow reactor having first and second catalysts and providing a feed comprising HMF into the reactor. The feed is contacted with the first catalyst to produce furan dimethanol (FDM) which is contacted with the second catalyst to produce THFDM.