[Due to the increasing size of the archives, each topic page now contains only the prior 365 days of content. Access to older stories is now solely through the Monthly Archive pages or the site search function.]
Vertimass licenses ORNL ethanol-to-hydrocarbon conversion technology; overcoming the blend wall with drop-in fuels
March 07, 2014
Vertimass LLC, a California-based start-up company, has licensed an Oak Ridge National Laboratory (ORNL) technology that directly converts ethanol under moderate conditions at one atmosphere without the use of hydrogen into a hydrocarbon blend-stock for use in transportation fuels.
The technology developed by ORNL’s Chaitanya Narula, Brian Davison and Associate Laboratory Director Martin Keller uses an inexpensive zeolite catalyst to transform ethanol into a blend-stock consisting of a mixture of C3 – C16 hydrocarbons containing paraffin, iso-parrafins, olefins, and aromatic compounds with a calculated motor octane number of 95. Fractional collection of the fuel product allows for the different fractions to be used as blend-stock for gasoline, diesel, or jet fuel.
MIT researchers devise simple catalytic system for fixation and conversion of CO2
March 05, 2014
Researchers at MIT have devised a simple, soluble metal oxide system to capture and transform CO2 into useful organic compounds. More work is needed to understand and to optimize the reaction, but this approach could offer an easy and inexpensive way to recapture some of the carbon dioxide emitted by vehicles and power plants, says Christopher Cummins, an MIT professor of chemistry and leader of the research team.
The new reaction, described in an open access paper in the RSC journal Chemical Science, transforms carbon dioxide into a negatively charged carbonate ion, which can then react with a silicon compound to produce formate, a common starting material for manufacturing useful organic compounds. This process relies on the simple molecular ion molybdate: an atom of the metal molybdenum bound to four atoms of oxygen.
New nickel-gallium catalyst could lead to low-cost, clean production of methanol; small-scale, low-pressure devices
March 03, 2014
Scientists from Stanford University, SLAC National Accelerator Laboratory and the Technical University of Denmark have identified a new nickel-gallium catalyst that converts hydrogen and carbon dioxide into methanol at ambient pressure and with fewer side-products than the conventional catalyst. The results are published in the journal Nature Chemistry.
The researchers identified the catalyst through a descriptor-based analysis of the process and the use of computational methods to identify Ni-Ga intermetallic compounds as stable candidates with good activity. After synthesizing and testing a series of catalysts, they found that Ni5Ga3 is particularly active and selective. Comparison with conventional Cu/ZnO/Al2O3 catalysts revealed the same or better methanol synthesis activity, as well as considerably lower production of CO.
Researchers at Berkeley and Argonne labs discover highly active new class of nanocatalysts for fuel cells; more efficient, lower cost
February 28, 2014
A team led by researchers at Berkeley and Argonne National Labs have discovered a new class of bimetallic nanocatalysts for fuel cells and water-alkali electrolyzers that are an order of magnitude higher in activity than the target set by the US Department of Energy (DOE) for 2017.
The new catalysts, hollow polyhedral nanoframes of platinum and nickel (Pt3Ni), feature a three-dimensional catalytic surface activity that makes them significantly more efficient and far less expensive than the best platinum catalysts used in today’s fuel cells and alkaline electrolyzers. This research, a collaborative effort between DOE’s Lawrence Berkeley National Laboratory (Berkeley Lab) and Argonne National Laboratory (ANL), is reported in the journal Science.
Computational first-principles approach identifies dozens of new platinum-group alloys
January 07, 2014
Researchers from Duke University, Brigham Young University, and Carnegie Mellon University have used high-throughput first-principles calculations to identify dozens of platinum-group alloys (binary systems of the platinum-group metals—PGMs—with the transition metals) that were previously unknown but that could prove beneficial in a wide range of applications.
The platinum-group metals (PGMs)—osmium, iridium, ruthenium, rhodium, platinum, and palladium—play essential roles in a wide variety of industrial applications. The primary application of PGMs is in catalysis, where they are core ingredients in the chemical, petroleum, and automotive industries. Although are essential, they are also very costly.
Converting glycerol from biodiesel production into bio-gasoline
December 16, 2013
A team at the University of Idaho has demonstrated that glycerol, a byproduct from biodiesel production, could be used as a substrate for producing drop-in gasoline-range biofuel. In a paper published in the ACS journal Energy & Fuels, Guanqun Luo and Armando G. McDonald describe their study of converting methanol (MTG) and a mixture of methanol and glycerol (MGTG) into gasoline-range hydrocarbons using a bench-top, fixed-bed microreactor.
The MTG- and MGTG-generated liquids showed a similar composition, mainly methylbenzenes, to regular gasoline, and composition changed as the reaction proceeded to favor heavier aromatics.
University of Houston team demonstrates new efficient solar water-splitting catalyst for hydrogen production
Researchers from the University of Houston (UH) have developed a cobalt(II) oxide (CoO) nanocrystalline catalyst that can carry out overall water splitting with a solar-to-hydrogen efficiency of around 5%. They report on their work in a paper in the journal Nature Nanotechnology.
Corresponding author Jiming Bao, an assistant professor in the Department of Electrical and Computer Engineering at UH, said photocatalytic water-splitting experiments have been tried since the 1970s, but this was the first to use cobalt oxide and the first to use neutral water under visible light at a high energy conversion efficiency without co-catalysts or sacrificial chemicals.
Axens, IFPEN and Michelin launch research partnership on synthetic rubber production channel using biomass; €52M over 8 years
November 11, 2013
|Overview of BioButterfly process steps. Click to enlarge.|
Axens, IFP Energies nouvelles (IFPEN) and Michelin have launched a plant chemistry research partnership that aims to develop and bring to market a process for producing bio-sourced butadiene, or bio-butadiene. Butadiene is a chemical intermediate derived from fossil resources that is used in the production of synthetic rubber. Some 60% of global output is for the tire industry.
In response to the need to find sustainable alternative sourcing channels for elastomers, the BioButterfly process will make it possible to produce innovative, more environmentally-friendly synthetic rubber. The bio-butadiene produced will support continued innovation in procuring high performance rubber for tires.
Battelle evaluating pilot-scale mobile catalytic pyrolysis unit to convert biomass to bio-oil
November 08, 2013
Battelle researchers have developed a mobile catalytic pyrolysis unit that converts biomass materials such as wood chips or agricultural waste into bio-oil. As currently configured, the Battelle-funded unit converts one ton of pine chips, shavings and sawdust into as much as 130 gallons of wet bio-oil per day.
The bio-oil then can be upgraded by hydrotreatment into a gas/diesel blend or jet fuel. Conversion of the bio-oil to an advanced biofuel is a key element of Battelle’s (earlier post)—and many others’—research. Testing of the bio-based gasoline alternative produced by Battelle suggests that it can be blended with existing gasoline and can help fuel producers meet their renewable fuel requirements.
JCAP researchers propose protocol for standardized evaluation of OER catalysts for solar-fuel systems
November 03, 2013
|Protocol for measuring the electrochemically active surface area, catalytic activity, stability, and Faradaic efficiency of heterogeneous electrocatalysts for OER. Credit: ACS, McCrory et al. Click to enlarge.|
Electro-catalytic water splitting to produce hydrogen and oxygen is a key element of solar-fuels devices; identifying efficient catalysts for the oxygen evolution reaction (OER) is critical to their realization. (The OER is efficiency-limiting for direct solar and electrolytic water splitting, rechargeable metal-air batteries, and regenerative fuel cells. Earlier post.) However, notes a team of researchers from the Joint Center for Artificial Photosynthesis at Caltech, current methods employed to evaluate oxygen-evolving catalysts are not standardized, making it difficult to compare the activity and stability of these materials.
To address this issue, the researchers are proposing a protocol to evaluate the activity, stability, and Faradaic efficiency of electro-deposited oxygen-evolving electrocatalysts. In particular, they focus on methods for determining electrochemically active surface area and measuring electrocatalytic activity and stability under conditions relevant to an integrated solar water-splitting device. A paper on their work is published in the Journal of the American Chemical Society.
UNIST team develops simple way to synthesize new metal-free electrocatalysts for oxygen reduction reaction (ORR)
October 29, 2013
|Overall Scheme for doped graphene oxide Copyright: UNIST. Click to enlarge.|
A research team from Ulsan National Institute of Science and Technology (UNIST), S. Korea, has developed a high-performance, stable and metal-free electrocatalyst for the oxygen reduction reaction (ORR). A paper on their work is published in the RSC journal Nanoscale.
The oxygen reduction reaction (ORR) is an important reaction in energy conversion systems such as fuel cells and metal–air batteries; electrocatalysts for oxygen reduction are critical components that may dramatically enhance the performance such systems. Carbon nanomaterials doped with heteroatoms are highly attractive materials for use as electrocatalysts by virtue of their excellent electrocatalytic activity, high conductivity, and large surface area.
Duke team develops new core-shell copper nanowire catalyst for efficient water oxidation for solar fuels
October 25, 2013
|A transparent film of copper nanowires was transformed into an electrocatalyst for water oxidation by electrodeposition of Ni or Co onto the surface of the nanowires. Chen et al. Click to enlarge.|
A team led by Benjamin J. Wiley at Duke University has introduced a new electrocatalyst for water oxidation consisting of a conductive network of core-shell nanowires that is just as efficient as conventional metal oxide films on indium tin oxide (ITO) and a great deal more transparent and robust. A paper on their work is published in the journal Angewandte Chemie.
Water oxidation (2H2O → O2 + 4e- + 4H+) is a key step for converting solar energy into chemical fuels. Nickel and cobalt oxides are attractive anode materials for the oxidation of water because they are readily available and demonstrate high catalytic activity. For use in photoelectric synthesis cells, in which chemical conversions are driven by light, the oxides are typically electrodeposited onto ITO substrates. ITO is used because of its high transmittance and low sheet resistance.
Researchers develop viable catalysts for reforming of heavy gas oil to hydrogen
October 14, 2013
One approach to delivering hydrogen for the stacks in fuel cell vehicles is via the on-board reforming of hydrocarbon fuels; such an approach obviates the need for on-board hydrogen gas storage technology and leverages the existing liquid fuels infrastructure. However, using more refined low-sulfur hydrocarbon fuels can add to the overall cost of the system. Less refined fuels—such as heavy gas oil—would be less expensive; however, the higher levels of sulfur in the fuels could prove problematic for catalysts.
Now, researchers in S. Korean and Japan have synthesized hollow fiber catalysts networked with perovskite nanoparticles for the production of hydrogen from heavy gas oil reforming, some of which showed high efficiency for H2 production with substantial durability under high concentrations of S, N, and aromatic compounds. Their findings are reported in an open access paper in the journal Scientific Reports.
New family of non-precious metal catalysts outperform platinum for oxygen-reduction reaction in fuel cells at 10% the production cost
September 23, 2013
|ORR polarisation curves of Pt/C and FeCo-OMPC catalysts before and after 10,000 potential cycles in O2-saturated 0.1 M HClO4. Potential cycling was carried out from 0.6 to 1.0 V vs. RHE at 50 mV s−1. Cheon et al. Click to enlarge.|
Researchers from Ulsan National Institute of Science and Technology (UNIST), Korea Institute of Energy Research (KIER), and Brookhaven National Laboratory have discovered a new family of non-precious metal catalysts based on ordered mesoporous porphyrinic carbons (M-OMPC) with high surface areas and tunable pore structures. Porphyrins are any of a class of heterocyclic compounds containing four pyrrole rings arranged in a square.
These catalysts exhibit better performance than platinum in the oxygen-reduction reaction (ORR) important for fuel cells at 10% of the production cost of a platinum catalyst, the team said. The finding, described in an open access paper in Nature’s Scientific Reports, is potentially a step towards reducing the cost of fuel cell technology—one of the impediments to widespread commercialization.
ARPA-E awarding $3.5M to Berkeley Lab project to develop novel enzymatic gas-to-liquids pathway
September 22, 2013
On 19 September, the Advanced Research Project Agency-Energy (ARPA-E) awarded $34 million to 15 projects to find advanced biocatalyst technologies that can convert natural gas to liquid fuel for transportation. (Earlier post.) The largest award in the technical area of High-Efficiency Biological Methane Activation in the new program, (Reducing Emissions using Methanotrophic Organisms for Transportation Energy—REMOTE, earlier post), provides $3.5 million to a team led by Dr. Christer Jansson at Lawrence Berkeley National Laboratory (LBNL) to work on a novel methylation process to convert natural gas to liquid transportation fuels.
The project, called “Enzyme Engineering for Direct Methane Conversion,” involves designing a novel enzyme—a PEP methyltransferase (PEPMase)—by engineering an existing enzyme to accept methane instead of carbon dioxide. This methylation process, which does not exist in nature, will be used as the basis for the gas-to-liquids pathway.
New core-shell bi-layer nanocatalyst tolerant to CO; potential for low-temperature fuel cells with reformates
September 21, 2013
Researchers at Brookhaven National Laboratory have created a high-performing bi-layer durable nanocatalyst that is tolerant to carbon monoxide, a catalyst-poisoning impurity in hydrogen derived from natural gas. The novel core-shell structure—ruthenium coated with platinum—resists damage from carbon monoxide as it drives the energetic reactions central to electric vehicle fuel cells and similar technologies.
The single crystalline Ru cores with well-defined Pt bilayer shells address the issues in using a dissolution-prone metal, such as ruthenium, to alleviate carbon monoxide poisoning, and thereby open the door for commercialization of low-temperature fuel cells that can use inexpensive reformates (H2 with CO impurity) as the fuel, the authors noted. Their paper is published in the journal Nature Communications.
MIT team discovers new family of materials with best performance yet for oxygen evolution reaction; implications for fuel cells and Li-air batteries
September 19, 2013
|A diagram of the molecular structure of double perovskite shows how atoms of barium (green) and a lanthanide (purple) are arranged within a crystalline structure of cobalt (pink) and oxygen (red). Grimaud et al. Click to enlarge.|
MIT researchers have found a new family of highly active catalyst materials that provides the best performance yet in the oxygen evolution reaction (OER) in electrochemical water-splitting—a key requirement for energy storage and delivery systems such as advanced fuel cells and lithium-air batteries.
The materials, double perovskites (Ln0.5Ba0.5)CoO3−δ (Ln=Pr, Sm, Gd and Ho), are a variant of a mineral that exists in abundance in the Earth’s crust. Their remarkable ability to promote oxygen evolution in a water-splitting reaction is detailed in a paper appearing in the journal Nature Communications. The work was conducted by Dr. Yang Shao-Horn, the Gail E. Kendall Professor of Mechanical Engineering and Materials Science and Engineering; postdoc Alexis Grimaud; and six others.
New route for upgrading bio-oil to biogasoline via molecular distillation and catalytic cracking
September 18, 2013
|Bio-oil-graded upgrading route based on molecular distillation and catalytic cracking. Credit: ACS, Wang et al. Click to enlarge.|
A team at Zhejiang University, China, has developed a novel cracking technology for the upgrading of bio-oil, produced by the fast pyrolysis of biomass, to biogasoline. In a paper published in the ACS journal Energy & Fuels, they report that the co-cracking of the distilled fraction (DF) from bio-oil molecular distillation and ethanol produced a well-defined gasoline phase, and that both increasing the reaction temperature and adopting pressurized cracking benefited the yield and quality of this gasoline phase.
Under optimum reaction temperature and pressure, co-cracking of the DF and ethanol, with different weight ratios, all generated high-quality gasoline phases. Under 400 °C and 2 MPa, co-cracking of DF and ethanol with a weight ratio of 2:3 produced a high gasoline phase yield of 25.9 wt %; the hydrocarbon content in this gasoline phase was 98.3%. CO2, CO, and C3H8 (propane) were the main gaseous products, and a low coke yield of 3.2 wt % was achieved.
PNNL team finds correlation between reaction mechanism for zeolite SCR catalyst for NOx aftertreatment and bacterial enzyme catalysis
September 11, 2013
|Computer model of Cu-SSZ-13 shows nitric oxide (ball-and-stick) interacting with a positively charged copper ion (copper ball) at an unexpected angle (red dotted lines). Photo courtesy of Kwak et al. Click to enlarge.|
A team of researchers in the Institute for Integrated Catalysis at Pacific Northwest National Laboratory led by chemist János Szanyi has proposed a reaction mechanism for a highly active zeolite catalyst (Cu-SSZ-13) used in selective catalytic reduction (SCR) NOx aftertreatment systems for diesel emissions. A paper on their work is published in the journal Angewandte Chemie International Edition.
Although the catalyst is in use, exactly how it converts NOx to nitrogen and water with the help of ammonia (urea) hasn’t been entirely clear. The new research finds that the catalyst works much the same way that similar bacterial enzymes do: by coming at the target from the side rather than head on. The finding provides insight into how to make better catalytic converters.
NRL researchers optimizing two-step process for synthesis of jet-fuel-range hydrocarbons from CO2
September 09, 2013
Researchers at the US Naval Research Laboratory (NRL) are investigating an optimized two-step process for the synthesis of liquid hydrocarbons in the jet fuel range from CO2 and hydrogen. The process, reported in the ACS journal Energy & Fuels, could leverage a recently reported process, also developed by NRL, to recover CO2 from sea water.
CO2 is 140 times more concentrated in seawater than in air on a weight per volume basis (g/mL), the authors note. With scaling and optimization of this CO2 recovery technology already underway, NRL researchers and others are working on new and improved catalysts for the conversion of CO2to useful hydrocarbons.
Berkeley Lab researchers at JCAP develop unique semiconductor/catalyst construct for production of H2 from sunlight
August 30, 2013
Researchers with the US Department of Energy (DOE)’s Lawrence Berkeley National Laboratory (Berkeley Lab) working at the Joint Center for Artificial Photosynthesis (JCAP) have developed a method by which molecular cobalt-containing hydrogen production catalysts can be interfaced with a semiconductor that absorbs visible light.
Coupling the absorption of visible light with the production of hydrogen in one material enables the generation of a fuel simply by illuminating the photocathode, says Gary Moore, a chemist with Berkeley Lab’s Physical Biosciences Division and principal investigator for JCAP. “No external electrochemical forward biasing is required.” Moore is the corresponding author of a paper describing this research in the Journal of the American Chemical Society (JACS).
ORNL finding on surface properties of complex oxides films could lead to better batteries and catalysts
August 14, 2013
Researchers at Oak Ridge National Laboratory (ORNL), with colleagues from the Chinese Academy of Sciences and Fudan University, have discovered that key surface properties of complex oxide films are unaffected by reduced levels of oxygen during fabrication—an unanticipated finding with possible implications for the design of functional complex oxides.
The discovery, which may result in better batteries, catalysts, electronic information storage and processing devices, is reported in a paper published in the RSC journal Nanoscale.
New materials for bio-based hydrogen synthesis; synthetic biology enables spontaneous protein activation
August 13, 2013
Researchers at the Ruhr-Universität Bochum (RUB) (Germany), with colleagues from the MPI (Max Planck Institute) Mülheim and Université Grenoble, have discovered an efficient process for hydrogen biocatalysis. They developed semi-synthetic hydrogenases—hydrogen-generating enzymes—by adding the protein’s biological precursor to a chemically synthesized inactive iron complex.
From these two components, the biological catalyst formed spontaneously in a test tube, thus greatly simplifying the design and production of hydrogenases. The team reports on their work in a paper in the journal Nature Chemical Biology.
Bi-metal aerogel catalyst shows promise as high-efficiency, lower-platinum electrocatalyst for fuel cells
August 09, 2013
|Detailed structure of the platinum/palladium aerogel nanowires (alloy ratio: 50% platinum, 50% palladium) Source: PSI. Click to enlarge.|
Researchers from Germany and Switzerland have manufactured and characterized a novel aerogel catalyst that could significantly increase the efficiency and life of low-temperature polymer electrolyte fuel cells as well as reduce material costs by reducing the platinum loading required. A paper on their work appears in the journal Angewandte Chemie.
Using a three-dimensional aerogel made of a platinum-palladium alloy, they were able to increase the catalytic activity for oxygen reduction at the positive electrode of a hydrogen fuel cell five-fold compared to normal catalysts made of platinum on carbon supports—i.e., the same amount of oxygen can now be converted with only a fifth of the amount of precious metals. If this reduction of the necessary platinum load could be transferred onto an industrial scale, it would slash the production costs for these fuel cells.
Nitrogen-doped graphene nanoplatelets offer high catalytic performance in fuel cells and solar cells; possible replacement for Pt
July 23, 2013
Researchers in South Korea have developed a simple, low-cost and eco-friendly method of creating nitrogen-doped graphene nanoplatelets (NGnPs) with excellent catalytic performance in both dye-sensitized solar cells and fuel cells to replace conventional platinum (Pt)-based catalysts for energy conversion.
A paper on the work, carried out at Ulsan National Institute of Science and Technology (UNIST), is published in Scientific Reports. The UNIST team had previously reported that dry ball-milling can efficiently produce chemically modified graphene particles in large quantities. This new work dry ball mills graphite with nitrogen gas (N2), resulting in the direct fixation of N2 at the edges of graphene nanoplatelets (GnPs).
Researchers devise Pt electrocatalysts with greatly increased activity; potential for significant cuts in fuel cell cost
July 22, 2013
Researchers in Denmark and Germany have found that size-selected platinum (Pt) nanoclusters can reach extraordinarily high ORR (oxygen reduction reaction—a key reaction in hydrogen fuel cells) activities, especially in terms of mass-normalized activity, if deposited at high coverage on a glassy carbon substrate.
When tested in the laboratory, the mass specific activity of commercial Pt fuel cell catalysts is around 1 A mg-1Pt. The researchers, led by associate professor of chemistry Matthias Arenz at the University of Copenhagen, found one of their catalysts delivered almost 8 A mg-1Pt. Their finding on the role of particle proximity in the efficiency of the Pt ORR activity might enable a significant reduction in the use of platinum in fuel cells for a given power output, resulting in less expensive fuel cells. A paper on their work is published in the journal Nature Materials.
Dutch/Russian effort to commercialize new process to convert flared gas to gasoline via a DME pathway
July 16, 2013
The independent Dutch research organization TNO is working with the Russian A.V. Topchiev Institute for Petrochemical Synthesis (TIPS) on marketing a new technology developed by TIPS to convert flared gases into hydrocarbon fuels such as gasoline. The new method offers a range of benefits compared with the common, but nearly hundred-year old, Fischer-Tropsch process, the partners said.
The conventional way to make gasoline from gas is to convert the gas to a synthesis gas, then into methanol, followed by conversion to straight-chain hydrocarbons and finally via reforming into a high-octane hydrocarbon blend. The method developed by TIPS skips the conversion into methanol; the synthesis gas is converted into dimethylether (DME) as the step preceding the direct synthesis of branched hydrocarbons with a high octane number.
New molybdenum disulfide catalyst shows promise for lower cost hydrogen production
July 03, 2013
Researchers at the University of Wisconsin - Madison have developed MoS2 (molybdenum disulfide) nanosheet catalysts that deliver “dramatically” enhanced hydrogen evolution reaction (HER) catalysis for the production of hydrogen gas from water—albeit still lower than platinum. However the eventual ability to use such an inexpensive, abundant alternative instead of platinum for a catalyst material would reduce the cost of hydrogen production. Their results are published as a “Just Accepted” paper online in the Journal of the American Chemical Society.
Although traditionally used as a hydrodesulfurization catalyst, molybdenum disulfide (MoS2) is also of interest as an HER catalyst that exhibits promising hydrogen evolution activity in crystalline or amorphous materials, and molecular mimics. (Earlier post.) However, the catalytic HER performance of MoS2 is currently limited by the density and reactivity of active sites, poor electrical transport, and inefficient electrical contact to the catalyst, the authors noted.
Researchers discover method enabling use of iron nanoparticle catalyst for hydrogenation, replacing heavy metals
June 28, 2013
Researchers from McGill University, RIKEN (The Institute of Physical and Chemical Research, Wako, Japan) and the Institute for Molecular Science (Okazaki, Japan) have discovered a technique enabling the use of iron nanoparticles as a catalyst for the industrially important hydrogenation process, making it more environmentally friendly and less expensive.
Hydrogenation—which is used in a wide range of industrial applications, from food products, such as margarine, to petrochemicals, pharmaceuticals and biofuels—typically involves the use of heavy metals, such as palladium or platinum, to catalyze the chemical reaction. While these metals are very efficient catalysts, they are also non-renewable, costly, and subject to sharp price fluctuations on international markets.
New catalysts enable photocatalytic version of water gas shift reaction for H2 production
June 18, 2013
Researchers at the Univ. Politécnica de Valencia (Spain) have found that noble metal nanoparticles supported on titanium dioxide or cerium dioxide can catalyze the industrially important water gas shift (WGS) reaction for hydrogen production at ambient temperatures using visible light irradiation. An open access paper on their discovery is published in the RSC journal Energy and Environmental Science.
Currently, most hydrogen is produced via the steam reforming of natural gas, hydrocarbons and coal. Additional amounts of hydrogen are generated by the reaction of CO with water (the water gas shift reaction)—which also leads to the formation of CO2. WGS is an endothermic process typically carried out in industry at high temperatures (about 350 °C) with either an iron oxide- or copper-based catalyst to achieve almost complete CO conversion.
New metal-free ORR catalyst outperforms platinum in fuel cell
June 06, 2013
Researchers from South Korea, Case Western Reserve University and University of North Texas have synthesized new inexpensive and easily produced metal-free catalysts—edge-selectively halogenated graphene nanoplatelets (XGnPs)—that can perform better than platinum in oxygen-reduction reactions. The finding, detailed in an open access paper in Nature’s Scientific Reports, is a step toward eliminating what industry regards as the largest obstacle to large-scale commercialization of fuel cell technology—the high cost and insufficient supply of platinum catalysts.
The XGnPs, which were produced using a simple ball-milling method, were tested as cathode electrodes of fuel cells and revealed “remarkable” electrocatalytic activities for ORR with high tolerance to methanol crossover/CO poisoning effects and longer-term stability than those of the pristine graphite and commercial Pt/C electrocatalysts. In initial tests, a cathode coated with one form of catalyst—graphene nanoparticles edged with iodine—generated 33% more current than a commercial cathode coated with platinum.
New LANL non-precious metal ORR catalyst can out-perform platinum; possible enabler for economical Li-air batteries, fuel cells
June 05, 2013
|ORR polarization plots after 5,000 cycles in O2-saturated electrolyte comparing the new catalyst and a platinum catalyst. Chung et al.Click to enlarge.|
Scientists at Los Alamos National Laboratory (LANL) have designed a new type of nitrogen-doped carbon-nanotube catalyst that shows the highest oxygen reduction reaction (ORR) activity in alkaline media of any non-precious metal catalyst developed to date. When used at a sufficiently high loading, this stable catalyst also outperforms the most active platinum-based catalysts, the team found.
The new catalyst, reported in an open source paper in Nature Communications, could pave the way for reliable, economical metal-air batteries and alkaline fuel cells, providing for practical use of wind- and solar-powered electricity, as well as enhanced hybrid and electric vehicles.
ITOCHU invests in Flint Hills/Benefuel biodiesel project in US
Japan-based ITOCHU Corporation has invested in a 50-million-gallon/year, next-generation (inedible feed stock base) biodiesel fuel (BDF) project, which Flint Hills Resources LLC (FHR), a leading US refining, biofuel and chemicals company, and Benefuel Inc, developer of a solid-state biodiesel catalyst and process (earlier post), are jointly developing in Beatrice, Nebraska.
Benefuel and FHR have an exclusive agreement to develop and operate US-based biodiesel projects using Benefuel’s ENSEL technology. The joint venture—Duonix, LLC—is actively developing the first project, which is a retrofit of the 50-million-gallon-per-year facility in Beatrice, Nebraska. The facility was acquired by FHR out of bankruptcy and has since been transferred to Duonix. The Beatrice plant will continue to be operated by FHR.
U. Minn. team proposes strategy for automated selection of optimal biomass-derived fuel blends and synthesis paths
May 07, 2013
|Proposed strategy for connecting automated network generation and optimization. Credit: ACS, Marvin et al. Click to enlarge.|
Researchers at the University of Minnesota are proposing a novel strategy that simultaneously identifies (a) the most desirable biomass-derived chemical products for an application of interest, such as fuels, and (b) the corresponding synthesis routes.
In a paper published in the ACS journal Energy & Fuels, they describe the strategy, and then apply it to identify potential renewable oxygenates and hydrocarbons obtained from heterogeneous catalysis of biomass that can be blended with gasoline to satisfy ASTM specifications.
Brookhaven team develops molybdenum-soy catalyst that rivals performance of noble metals for hydrogen production
April 24, 2013
Researchers at the US Department of Energy’s Brookhaven National Laboratory (BNL) have developed a low-cost, stable, effective catalyst made from earth-abundant molybdenum and common soybeans (MoSoy).
In a paper published in the RSC journal Energy & Environmental Science, the team reports that the catalyst—composed of a catalytic β-Mo2C phase and an acid-proof γ-Mo2N phase, drives the hydrogen evolution reaction (HER) with low overpotentials, and is highly durable in a corrosive acidic solution over a period exceeding 500 hours. When supported on graphene sheets, the MoSoy catalyst exhibits very fast charge transfer kinetics, and its performance rivals that of noble-metal catalysts such as platinum (Pt) for hydrogen production.
PNNL solar thermochemical reaction system can reduce fuel consumption in natural gas power plants by about 20%; future potential for transportation fuels
April 11, 2013
|PNNL’s thermochemical conversion device is installed in front of a concentrating solar power dish. Photo: PNNL. Click to enlarge.|
A new concentrating solar power system developed by Pacific Northwest National Laboratory (PNNL) can reduce the fuel consumption of a modified natural-gas combined-cycle (NGCC) power plant by about 20%. The system converts natural gas into syngas—with higher energy content than natural gas—using a thermochemical conversion device installed in front of a concentrating solar power dish. The power plant then combusts the more energy dense syngas to produce electricity.
PNNL’s system uses a mirrored parabolic dish to direct sunbeams to a central point, where the thermochemical device uses the solar heat to produce syngas form natural gas. About four feet long and two feet wide, the device contains a chemical reactor and several heat exchangers. Concentrated sunlight heats up the natural gas flowing through the reactor’s channels, which hold a catalyst that helps turn natural gas into syngas.
New catalysts convert ethanol to butanol with high selectivity; potential low-cost upgrade for ethanol plants
Researchers at the University of Bristol (UK) have developed a new family of catalysts that enables the conversion of ethanol into n-butanol—a higher alcohol with better characteristics for transportation applications than ethanol—with selectivity of more than 95% at good conversion. The team presented a pair of papers on their work at the Spring meeting of the American Chemical Society this week in New Orleans.
While butanol has emerged as a potential sustainable liquid fuel replacement for gasoline, development of biosynthetic pathways for its synthesis are challenged by very low conversion and modest selectivity, they noted. Although catalytically upgrading the more readily available bioethanol to butanol is theoretically attractive, this has been hampered by modest selectivity in most cases.
EBEI researchers shed light on how multiple cellulase enzymes attack cellulose; potential avenue to boosting sugar yields for biofuels
April 08, 2013
|PALM enables researchers to quantify how and where enzymes are binding to the surface of cellulose in heterogeneous surfaces, such as those in plant cell walls. Source: Berkeley Lab. Click to enlarge.|
Researchers with the Energy Biosciences Institute, University of California, Berkeley have provided insight into how multiple cellulase enzymes attack cellulose, potentially yielding a way to improve the collective catalytic activity of enzyme cocktails that can boost the yields of sugars for making fuels.
Increasing the sugar yields from cellulosic biomass to help bring down biofuel production costs is essential for the widespread commercial adoption of these fuels. A paper on their work is published in Nature Chemical Biology.
Primus Green Energy to support gas-to-liquids research at Princeton University; comparing STG+ to other GTL platforms
March 28, 2013
|Schematic diagram of the Primus STG+ process. Click to enlarge.|
Primus Green Energy Inc., developer of a proprietary process to produce gasoline and other fuels from biomass and/or natural gas (earlier post), will provide financial support to engineers at Princeton University for general research on synthetic fuels, which will include assessments of various gas-to-liquids (GTL) technologies—including Primus’ own STG+—for sustainability and economic viability.
STG+ technology converts syngas into drop-in high-octane gasoline and jet fuel with a conversion efficiency of ~35% by mass of syngas into liquid transportation fuels (the highest documented conversion efficiency in the industry) or greater than 70% by mass of natural gas. The fuels produced from the Primus STG+ technology are very low in sulfur and benzene compared to fuels produced from petroleum, and they can be used directly in vehicle engines as a component of standard fuel formulas and transported via the existing fuel delivery infrastructure.
UNSW team develops bio-inspired catalytic approach to chemical reduction for production of fuels and chemicals
March 25, 2013
Scientists at the University of New South Wales (Australia) have developed a new bio-inspired method for carrying out chemical reduction—an industrial process used to produce fuels and chemicals. A report on their work is published in the journal Angewandte Chemie.
Chemical reduction involves the addition of electrons to a substance, and is the basis of making many fuels, including the sugars that plants produce during photosynthesis. The catalyst designed by the team led by Associate Professor Stephen Colbran of the UNSW School of Chemistry mimics the activity of naturally occurring metallo-(de)hydrogenase enzymes that catalyse reduction, such as alcohol dehydrogenase in yeast, that helps produce alcohol from sugar.
Univ. of Calgary team developing nanocatalysts for underground upgrading of heavy oil and bitumen; possible “next generation” of oil sands production
|Total injected hot fluid and total produced liquid for the nanocatalyst experiments at temperatures of 320 and 340 °C. Credit: ACS, Hashemi et al. Click to enlarge.|
Researchers at the University of Calgary are developing ultra-dispersed (UD) nanocatalysts for the in situ upgrading of heavy oil and bitumen from deep reservoirs. Such an “underground refinery” approach is one of the alternatives to surface upgrading that may become the next-generation of oil sands industry improvement, they suggest in a paper published in the ACS journal Energy & Fuels.
One of the challenges of such an approach is the placement of the catalyst deep into the heavy oil plume by transporting a catalyst suspension through the sand medium. In their paper, they report that water-in-vacuum gas oil microemulsions containing trimetallic (W, Ni, and Mo) ultradispersed colloidal nanoparticles could penetrate inside the porous medium and react with the bitumen, resulting in enhanced recovery.
Yale team develops new silver-palladium core-shell catalyst for direct alcohol fuel cells
March 19, 2013
|The core-shell silver-palladium catalyst. Source: Yale. Click to enlarge.|
Yale researchers have synthesized a silver-palladium core-shell catalyst supported on multi-walled carbon nanotubes (Ag@Pd/MWNTs) for use in fuel cells. The new platinum-free catalysts are are highly active and alcohol-tolerant for oxygen reduction reactions (ORR) in alkaline media. A paper on their work is published in the journal Applied Catalysis B.
The new, platinum-free catalyst has a unique core-shell structure; the thin shell is palladium, the core silver. This allows for higher catalytic activity and greater tolerance for impurities than standard platinum-based catalysts. Particles of silver coated with palladium cover the surface of multi-walled carbon nanotubes, promoting the reduction of oxygen over the oxidation of alcohol.
Researchers use LCLS to get real-time view of chemical reaction; important insight into how catalysts work
March 15, 2013
An international team of researchers has used the ultrafast, ultrabright X-ray pulses of the Linac Coherent Light Source (LCLS) at the US Department of Energy’s (DOE) SLAC National Accelerator Laboratory (earlier post) to gain unprecedented views of a catalyst in action, an important step in the effort to develop cleaner and more efficient energy sources. A paper on their work is published in the journal Science.
The scientists used LCLS, together with computerized simulations, to probe the electronic structure of CO molecules as their chemisorption state on a ruthenium catalyst sample changed upon exciting the substrate. The study revealed surprising details of a short-lived early state in the chemical reaction, offering important clues about how catalysts work and launching a new era in probing surface chemistry as it happens.
Stanford GCEP awards $6.6M to 7 projects; focus on combining energy conversion with carbon-neutral fuel production
March 13, 2013
Stanford’s Global Climate and Energy Project (GCEP) is awarding $6.6 million to seven research teams—six from Stanford and one from Carnegie Mellon University—to advance research on technologies for renewable energy conversion to electricity or fuels and for capturing CO2 emissions and converting CO2 to fuels.
The 7 awards bring the total number of GCEP-supported research programs to 104, with total funding of approximately $125 million since the project’s launch in 2002.
IACS team develops high-performing bio-inspired electrocatalyst for hydrogen generation in an aqueous medium
March 11, 2013
Researchers from the Indian Association for the Cultivation of Science (IACS), an autonomous—and the oldest—research institute in India, have developed a high-performing bio-inspired catalyst (an Fe−Fe hydrogenase mimic immobilized on graphite surfaces) for electrocatalytic hydrogen generation in an aqueous medium.
In a paper published in the journal ACS Catalysis, they report that the catalyst shows a turnover frequency of 6,400 s−1 at −0.5 V and an onset potential of −0.36 V vs NHE (normal hydrogen electrode, an early standard for zero potential). Prolonged electrolysis shows that the catalyst has a turnover number ≫108 and a Faradaic efficiency > 95%. Even at pH 2, more than 400 s−1 is obtained. The catalyst can be immobilized on inexpensive carbon electrodes, such as those used in domestic Zn-carbon dry batteries, to generate H2 from acid aqueous solutions.