When Less Is More: Fewer Proton Relays Improve Catalytic Rates
By directly comparing three closely related catalysts, CME scientists established that hydrogen production speed and efficiency are influenced by the molecules' structure and proton relay arrangement, not the total number relays.
How to Store Sunlight on a Tight Energy Budget: Add More Protons
Making hydrogen economically demands a quick, efficient reaction. Creating that reaction demands a catalyst. CME scientists found that a proton and water-packed environment lets the catalyst work 50 times faster—without added energy.
Adventure Planning, Catalyst Style
At PNNL, scientists have elaborated on a strategy to map the catalytic route. Scientists can now explore design decisions with molecular catalysts that store or release energy from the chemical bond in dihydrogen (H2).
Energy Storage @ PNNL Webinar Series | August
The August Energy Storage Webinar Series focuses on pumped storage hydrogen and will highlight the role and value of it in supporting our clean energy future as well as challenges faced with deployment.
Advantage: Water
When water comes in for a landing on the common catalyst titanium oxide, it splits into hydroxyls just under half the time. Water's oxygen and hydrogen atoms shift back and forth between existing as water or hydroxyls, and water has the sli
CONVERSION OF POLYMERS IN MIXTURES OF ORGANIC COMPOUNDS AT SUPERCRITICAL CONDITIONS (iEdison No. 0685901-22-0219 - VOIDED - reporting to be done by BASF, iEdison No. 4579201-22-0001)
A process that converts polymers (e.g., waste polyolefins) into useful mixtures of hydrocarbons using supported metal catalysts (i.e., transition metal catalysts supported on carbon or metal oxides). The polymers are solubilized in mixtures of organic compounds that are subjected to corresponding supercritical conditions. Two examples are described in the following. 1) Polymer and a stream of light hydrocarbons are contacted in a mixer to dissolve the polymer in a liquid phase. The stream with dissolved polymer is mixed with hydrogen and introduced to a fixed bed reactor containing the supported metal catalyst. The mixing step and the reactor are held, at least, at the temperature and pressure needed to reach supercriticality of the mixture of hydrocarbons dissolving the polymer. The effluent of the reactor is separated in two stages. The first one recovers hydrogen and gas products, whereas the second stage produces the stream of light hydrocarbons to dissolve the polymer and the stream of liquid products in the initial stage of the process. 2) Polymer is introduced, via an extruder, to a reactor containing a slurry of the supported catalyst. Hydrogen is also feed into the reactor. The pressure and temperature in this reactor are chose to keep the supercriticality of the liquid inside the reactor. The gas phase, which contains unreacted hydrogen and gas products, is extracted from the reactor and treated to recover hydrogen. The liquid/supercritical phase leaves the reactor for a separation step that separates the liquid products from the light products that are cycled back to the slurry reactor. In both cases polyolefins are converted to alkanes according to the following general reactions: (C2H4)m + xH2 → x(CnH2n+2) (C3H6)m + xH2 → x(CnH2n+2)
SYSTEMS AND METHODS OF LONG-DURATION ENERGY STORAGE AND REGENERATION OF ENERGY-BEARING REDOX PAIRS
Described herein are systems and methods of storing and delivering electrical using hydrogen at low-cost and for long-durations. The systems and methods use energy-bearing redox pairs that electrochemically bear energy through decoupled hydrogen and oxygen consumption and/or evolution reactions, which are typically associated with fuel cells. Each species of the energy-bearing redox pair is associated with a standard electrode potential within a water electrolysis voltage window for the electrolyte solution. Electrical energy delivery, hydrogen generation, electrolyte regeneration, or combinations thereof can be performed by logically or physically separated unit operations in a continuous manner, batch manner, or semi-batch manner facilitated by the energy-bearing redox pair.
Conversion of 2,3-butanediol to 2-butanol, olefins and fuels
Embodiments of an integrated method for step-wise conversion of 2,3-butanediol to 2-butanol, and optionally to hydrocarbons, are disclosed. The method includes providing an acidic catalyst, exposing a composition comprising aqueous 2,3-butanediol to the acidic catalyst to produce an intermediate composition comprising methyl ethyl ketone, providing a hydrogenation catalyst that is spatially separated from the acidic catalyst, and subsequently exposing the intermediate composition to the hydrogenation catalyst to produce a composition comprising 2-butanol. The method may further include subsequently exposing the composition comprising 2-butanol to a deoxygenation catalyst, and deoxygenating the 2-butanol to form hydrocarbons. In some embodiments, the hydrocarbons comprise olefins, such as butenes, and the method may further include subsequently exposing the hydrocarbons to a hydrogenation catalyst to form saturated hydrocarbons.
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.
Reactor, CO2 sorbent system, and process of making H2 with simultaneous CO2 sorption
A reactor and process for production of hydrogen gas from a carbon-containing fuel in a reaction that generates carbon dioxide is described. The carbon-containing fuel can be, for example, carbon monoxide, alcohols, oxygenates bio-oil, oil and hydrocarbons. In preferred embodiments, the reactor includes a monolithic structure form with an array of parallel flow channels. Methods of using the reactor are also described. In the reactor apparatus of the present invention, the catalytic reaction for hydrogen formation is conducted in conjunction with a carbonation reaction that removes carbon dioxide that is produced by the reactor. The carbonation reaction involves reaction of the carbon dioxide produced from the hydrogen formation reaction with metal oxide-based sorbents. The reactor apparatus can be periodically regenerated by regeneration of the sorbent. A carbon dioxide sorbent system comprising a solid sorbent and a eutectic, mixed alkali metal molten phase is also described.