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Pipe: Advanced tech

ORNL solid-state 5V Li-ion battery shows cycle life of 10,000, 90% capacity retention

Mon, 2014-10-20 05:30

Researchers from Oak Ridge National Laboratory have demonstrated a solid-state high-voltage (5 V) lithium battery with an extremely long cycle life of more than 10,000 cycles, with 90% capacity retention. The solid electrolyte enables the use of high-voltage cathodes and Li anodes with minimum side reactions, leading to a high Coulombic efficiency of 99.98+%.


ORNL solid-state Li-ion battery. Click to enlarge.

A paper on their work is published in the journal Advanced Energy Materials.

The energy stored in a battery of a given size is proportional to its voltage. Conventional lithium-ion batteries use organic liquid electrolytes that have a maximum operating voltage of 4.3 V; operation above this limit can cause short cycle life and serious safety concerns.

However, lithium-ion-conducting solid electrolytes could enable high-energy battery chemistries by circumventing safety issues of conventional lithium batteries with liquid electrolytes. Use of a solid electrolyte would simplify the use of a Li-metal anode with its high gravimetric energy density, for example.

Toyota, for one, is working on all-solid-state batteries as a mid-term advanced battery solution. (Earlier post.)

However, achieving the required combination of high ionic conductivity and a broad electrochemical window in solid electrolytes is a grand challenge for the synthesis of battery materials, members of the ORNL team noted in a paper published in the Journal of the American Chemical Society in 2013. (Earlier post.)

In this latest study, the Oak Ridge team replaced the conventional liquid electrolyte with a ceramic solid electrolyte of lithium phosphorus oxynitride (Lipon), and used a LiNi0.5Mn1.5O4 cathode and Li anode at a charge voltage to 5.1V. The solid state battery retained more than 90% of its original capacity after 10,000 cycles—equivalent to more than 27 years of life with a daily charge/discharge cycle.



Voltage profiles of the (a) LiNi0.5Mn1.5O4 solid-state lithium battery and (b) a LiNi0.5Mn1.5O4 liquid battery discharged at different rates. The battery was charged at C/10 before each discharge measurement. Li et al.Click to enlarge.

Resources

  • Juchuan Li, Cheng Ma, Miaofang Chi, Chengdu Liang, and Nancy J. Dudney (2014) “Solid electrolyte: the key for high-voltage lithium batteries,” Advanced Energy Materials doi: 10.1002/aenm.201401408

California ARB mods to ZEV regulations for IVMs would result in ~1.9% drop in total ZEV/TZEV units 2018-2025; no impact on air quality requirements

Mon, 2014-10-20 05:00

Early in September, the California Air Resources Board (ARB) announced it would consider in a 23-24 October meeting amendments to the Zero Emission Vehicle (ZEV) regulation that would modify the requirements for intermediate volume manufacturers (IVMs) selling into the state to allow them more time to come into the market. (Earlier post.)

Among the proposed changes were additional production lead time; a reduced compliance obligation (i.e., lower numbers of ZEVs); an opportunity to pool compliance obligations in ZEV states; and additional time to make up ZEV credit deficits. ARB staff estimated the proposed modifications could reduce total California deliveries of ZEVs (fuel cell and battery-electric vehicles) and TZEVs (Transition Zero Emission Vehicles, i.e., plug-in hybrids) by a total of about 26,000 units in the 2018 through 2025 timeframe out of the originally estimated 1,400,000 ZEVs and TZEVs for that period under the current regulation—i.e., by about 1.9%. (For MY 2026 and following, the reduced compliance obligation goes away.)

However, in the environmental analysis of the impact of the proposal, ARB noted that despite that projected reduction in ZEV and TZEV volume, because the ZEV amendments do not modify the in-place fleet average emission standards established by the other elements of the Advanced Clean Cars (ACC) package (earlier post), the air quality benefits of the ACC program as analyzed in 2011 will still be realized. In other words, the automakers still have to meet the fleet-based emissions requirements through their sales mix.

Last week, ARB staff issued a correction to the staff report on the changes issued as part of the September announcement; the earlier report had included text from an earlier version of the ZEV regulation, but the substance of the proposed amendments were not affected. However, the corrections do make the mechanism and impact more clear.

Background. ARB first adopted the ZEV Regulation in 1990. Its goal was and is to reduce the environmental impact of light-duty vehicles through the gradual introduction of ZEVs into the California fleet. The ZEV Regulation has been amended multiple times since its inception (most recently in January 2012 and October 2013) to reflect the pace of ZEV development, the emergence of new ZEV and near-ZEV technologies, and the need to provide clarifying language in an increasingly complex regulatory system.

The ZEV regulations, which are now part of California’s comprehensive Advanced Clean Cars (ACC) program which also includes the LEV III tailpipe emissions standard, is the “technology-forcing piece” of the state’s regulatory package for light-duty vehicles. Put another way, the ZEV regulations are driving to force the creation of a market for those vehicles in a much shorter time frame than would normally occur.

In an article in the Winter 2012 edition of Issues in Science and Technology, Daniel Sperling, founding Director of the Institute of Transportation Studies at the University of California, Davis (ITS-Davis) and ARB Board member; and Mary Nichols, ARB chairman, wrote:

Although climate change is a global problem that will require global action, transportation is essentially a local concern. International cooperation will be necessary to resolve problems in maritime and air transport, but action on cars and trucks can be taken at a national or state level.

In addition, although many experts say that the solution to our energy and climate problems is sending the correct price signals to industry and consumers, the transport sector’s behavior is highly inelastic in that it does not change significantly in response to changes in fuel prices, at least in the range that is politically acceptable. Europe has gasoline taxes over $4 per gallon and still finds the need to adopt aggressive performance standards for cars to reduce GHGs and oil use. These high fuel taxes certainly have an effect in reducing the average size and power of vehicles and leading people to drive less, but the resulting reductions in fuel use and GHGs still fall far short of the climate goals. … we are saying that much progress can, and probably will, be made in the transport sector in the next decade without international agreements and without getting the prices right. California is leading the way with policies that address three critical elements of the transportation system: vehicles, fuels, and mobility.

… California has a much more ambitious long-term policy commitment to EVs. In 1990, California adopted a zero-emission vehicle (ZEV) requirement, mandating that the seven largest automotive companies in California “make available for sale” an increasing number of vehicles with zero tailpipe emissions. The initial sales requirement was 2% of car sales in 1998 (representing about 20,000 vehicles at the time), increasing to 5% in 2001 and 10% in 2003.

The intent was to accelerate the commercialization of electric (and other advanced) technology, but batteries and fuel cells did not advance as fast as regulators hoped. The ZEV rule, after surviving industry litigation and multiple adjustments to reflect the uneven progress of hybrid, fuel cell, and battery technologies, now bears little resemblance to the original. Although some consider the ZEV mandate a policy failure, others credit it with launching a revolution in clean automotive technology. The actual numbers of vehicles sold to consumers as a result of the ZEV program are certainly not what CARB originally expected. Only a few thousand EVs were sold in the United States in the first decade of this century, most of them by start-ups such as Tesla.

… Could another policy have accomplished the same at less cost with less conflict? Who knows? What’s certain is that the ZEV program accelerated worldwide investment in electric-drive vehicle technology. The benefits of those accelerated investments continue to sprout throughout the automotive world, and California policy was the catalyst.

In May 2014, Nichols remarked that:

Everyone understands that going into new technology requires a commitment from auto companies, and they don’t normally turn a profit as quickly as everyone would like. But through a sustained commitment, they will. We’re coming to this collaboration as a way of helping companies. They’ve done a great job of producing great cars. We want them to succeed and want them to make money on this.

The current ZEV requirements for MY 2018 and following focus the program on ZEVs (battery-electric and fuel cell vehicles) and transitional ZEVs (TZEV)—typically plug-in hybrid electric vehicles (PHEV). ARB calculates that by 2025, compliance with the requirements will likely result in more than 15% of new sales being ZEVs and TZEVs.

One key to understanding the evolution of the ZEV regulations and the periodic tweaks made to it is to realize that while ARB establishes aggressive targets, it also works continuously with automakers to try to make achievable targets as well. This is the basis for the changes proposed for the Intermediate Volume Manufacturers (IVM) under consideration this week.

LVMs, IVMs, SVMs. ARB basically groups manufacturers into three buckets, based on their sales in the state: large volume (LVM); intermediate volume (IVM); and small volume (SVM). In the 2009 version of the ZEV regulations, SVMs (4,500 units or less) were not subject to the regulation; IVMs (4,501 to 60,000 units) were subject to the regulations, but could meet the whole requirement with PZEVs; and large volume manufacturers were subject to the full brunt of the ZEV regs.

The 2012 amendments to the ZEV reg adopted as part of the ACC package reduced the California sales upper bound for IVMs from 60,000 units to 20,000 per year beginning with the 2018 model year. They concurrently changed the IVMs’ ZEV obligations from being able to meet the mandate with super clean conventional partial zero emission vehicles (PZEVs) to transitional ZEVs (TZEVs or plug in hybrids).


An example of the impact of the 2012 amendments on automakers selling into California, using 2013 data from ARB, if the transition from IVM to LVM was based on sales numbers alone. With these type of sales numbers, the effect is to propel Subaru and Mazda into the LVM tier. Click to enlarge.

At the hearing for the 2012 amendments, the Board directed ARB staff to review how the new regulation affected IVMs who would suddenly find themselves transitioning into large volume manufacturer (LVM) requirements in the 2018 model year and to return to the Board by 31 December 2014, with a recommendation regarding more fair treatment of these manufacturers, ensuring all manufacturers would be successful in commercializing ZEV technologies.

ARB staff subsequently determined that vehicle sales alone is not sufficiently useful in assessing a manufacturer’s ability to bring advanced technology vehicles to market. After consulting with manufacturers, ARB staff decided that a better indicator of this ability is “robust global revenue in conjunction with the established manufacturer sales threshold”.

Staff then proposed a global revenue threshold of $40 billion (calculated from the average of the three consecutive fiscal years immediately preceding the determination). Specifically:

If, in the 2018, 2019, or 2020 fiscal years, an intermediate volume manufacturer would otherwise be subject to the requirements for a large volume manufacturer based on California production volume, and if the intermediate volume manufacturer’s average annual global revenues for that fiscal year, based upon the immediately prior and consecutive three fiscal years, is no greater than 40 billion dollars, then that manufacturer will continue to be considered an intermediate volume manufacturer conditional upon the manufacturer submitting to the Executive Officer, in writing, a report that demonstrates the types and numbers of ZEVs and TZEVs the manufacturer will deliver to California subsequent to the 2020 fiscal year to meet the requirements specified in subdivision 1962.2(b)(1)(A).

The global revenue test is only available to IVMs for the 2018 through 2020 model years. Beginning in the 2021 model year, a manufacturer exceeding the 20,000 vehicle threshold will need to prepare to bring ZEVs to market per the LVM requirements; ARB staff expects most IVMs will make ZEVs available for sale by the 2026 model year.

To accommodate product development lead time, ARB staff is proposing to extend the lead time to 5 three-year averages commencing once the first three-year average exceeds 20,000 vehicles. This provides IVMs a minimum of 5 years and a maximum of 7 years to bring a vehicle to market. This lead time is similar to the lead time provisions established for IVMs that transitioned to LVM status prior to 2018 in ZEV regulation versions prior to the 2012 amendments.

Reducing the ZEV percentage requirement. The current regulation establishes a minimum ZEV credit percentage requirement for manufacturers for the 2018 through 2025 and subsequent model years. The requirement represents the percentage of passenger cars and light duty trucks produced by a manufacturer and delivered for sale in California that must be ZEVs (credit-weighted based on the advanced vehicle technology chosen).

ZEV credit level by type Type Definition 2012-2104 credit level 2015-2107 credit level Type III ZEV 100+ mile range and fast refueling capable or 200 mile range 4 4 Type IV ZEV 200+ mile range and fast refueling capable 5 5 Type V ZEV 300+ mile range and fast refueling capable 7 9

As noted above, the current version of the ZEV Regulation allows an IVM to meet its pre-2018 model year ZEV obligation solely with partial zero emission allowance vehicles (PZEV). The regulation requires an IVM to begin delivering ZEVs in 2018 and subsequent model years.

In recognition of the lower number of vehicle models offered by the typical IVM (each of the IVM5 manufacturers offers 3 to 4 passenger car models while the LVMs offer an average of 12 passenger car models) and their lesser R&D capabilities, the ZEV Regulation allows an IVM to meet its entire ZEV obligation with TZEVs.

ARB staff then decided that the modification would compound the problem for IVMs:

While the intention was to decrease the burden on IVMs, the existing regulation has the practical effect of establishing a double hurdle for IVMs starting in 2018. First, an LVM has had several years to develop ZEV offerings and accrue credits from placement of those ZEVs. For example, LVMs received early introduction multipliers for vehicles introduced in advance of requirements. LVMs also received extended service credit for allowing consumers to either extend a lease or exercise a purchase option at the end of a lease. Neither of these opportunities exists for IVMs under the current regulation. In comparison, the IVMs face the comparatively difficult technological challenge of transitioning from compliance solely with PZEVs to compliance with TZEVs. Second, without the R&D and economic means that LVM have to concurrently develop both TZEVs and greater credit ZEVs, an IVM must plan to offer a significantly greater portion of its sales (potentially in excess of 40 percent in 2025) as TZEVs to meet its obligation. At a time when conventional hybrid market share in California is around 7 percent, this rate of participation in the advanced clean car market does not appear to be realistic for IVMs.—ARB staff ISOR

ARB staff thus proposed adjusting downward the total ZEV credit obligation for IVMs in the 2018 through 2025 model years. (This is under consideration this week.) The proposed obligation would be set at a credit level equivalent to the entire LVM optional (maximum) TZEV obligation plus one-fifth of the LVM pure ZEV obligation. This results in an IVM having an advanced technology vehicle sales percentage (based on a likely compliance scenario) more closely aligned to that of the LVMs.

Minimum ZEV credit requirement Model Year Credit percentage requirement, with proposed reduction for IVMs LVM IVM 2018 4.5% 2.9% 2019 7.0% 3.8% 2020 9.5% 4.7% 2021 12.0% 5.6% 2022 14.5% 6.5% 2023 17.0% 7.4% 2024 19.5% 8.3% 2025 22.0% 9.2% 2026 and subsequent 22.0% 22.0%


Reduced ZEV Credit Percentage Requirement for IVMs Size Credit type Model Years 2018-2026 and Subsequent ‘18 ‘19 ‘20 ‘21 ‘22 ‘23 ‘24 ‘25 ‘26+ LVM ZEV minimum 2 4 6 8 10 12 14 16 16 TZEV maximum 2.5 3 3.5 4 4.5 5 5.5 6 6 Total 4.5 7 9.5 12 14.5 17 19.5 22 22 IVMTZEV + 1/5 ZEV 2.9 3.8 4.7 5.6 6.5 7.4 8.3 9.2 22

Based on these revised percentages, ARB staff projected future sales, and found that under a likely compliance scenario California could see about 26,000 fewer ZEVs and TZEVs delivered in the 2018 through 2025 model years than would be delivered under the existing regulation: the 1.9% noted above.

Section 177 pooling (the ZEV states). Under Section 177 of the federal Clean Air Act, other states can opt in to California’s emission standards, including ZEV. Currently, nine states have done so: Connecticut, Maine, Maryland, Massachusetts, New Jersey, New York, Oregon, Rhode Island, and Vermont.

The 2012 changes established a new optional Section 177 State compliance path. Those provisions allow manufacturers to place extra ZEVs in the Section 177 states one and two years prior to the 2018 model year. In exchange for early placement of these “extra” ZEVs, manufacturers can pool credits across state lines within and between two regional pools. They also earn a reduced TZEV obligation in exchange for early ZEV placement.

Currently, ARB staff notes, only one IVM has a ZEV product or plans to bring a ZEV to market prior to the 2018 model year, so in practice only LVMs have been able to make use of these provisions. However, the IVMs say they need this same ability to pool ZEV and TZEV credits across state lines because some of them have few dealers in some of the Section 177 States.

To accommodate that, ARB staff is proposing additional flexibility for IVMs by allowing them to place extra ZEVs in Section 177 States in the two model years prior to the start of their LVM requirements should they transition into LVM status—but they may take an additional two years to place these extra ZEVs. The IVMs will also be allowed to pool TZEV credits to meet total annual percentage obligations in each Section 177 State. They will not be allowed a reduced TZEV obligation.

Dongfeng Nissan Dalian plant commences production; production hub for SUVs

Mon, 2014-10-20 04:15

The Dalian plant of Dongfeng Nissan Passenger Vehicle Company (DFL-PV) has commenced production, bringing production sites for Nissan cars in China—all bound for the domestic market—to four.

With a gross floor area of 1.32 million m2, the Dalian plant is being developed in two phases. The investment for the first phase totals RMB 5 billion (US$816.5 million), for an initial production capacity of 150,000 units per year. Upon completion of the second phase, the total capacity will expand to 300,000 units per year.

The Dalian plant is positioned as a production hub for Nissan SUVs. The manufacturing technology, quality and eco standard of the construction of the Dalian plant are aligned with the global standards of Nissan, while the factory management comes from existing Chinese plants.

This is a very exciting moment for all of us. It has been just 28 months since we announced the Dalian plant project, and we have overcome many challenges to realize this facility. We are proud of this achievement and poised to deliver high-quality SUVs from this plant to our customers. This plant will strengthen our competitiveness in China, which is the world's largest automotive market.—Susumu Uchikoshi, Managing Director of DFL-PV

The Dalian plant represents DFL-PV’s foothold in Northern China. Together with the Huadu (1st and 2nd) plants in Southern China, Xiangyang and Zhengzhou plants in Central China, DFL-PV is well positioned to provide vehicles throughout the country.

US transit agencies adopting lower-emissions diesel at faster rate than HD truck fleet

Sun, 2014-10-19 06:39

US transit agencies are adopting lower-emissions diesel technology at a faster percentage than the heavy-duty trucking fleet, said Ezra Finkin, the Director of Policy for the Diesel Technology Forum, at last week’s American Public Transportation Association (APTA) Expo Bus and Maintenance Technical Session in Houston. Nationally, 44% of the diesel transit buses meet or exceed the first EPA clean diesel standard—Model Year 2007 or newer—while 33% of the US truck fleet meet or exceed the standard.

The rate of adoption by transit agencies of clean diesel technology surprised us and is very significant, since transit agencies are at the forefront for evaluating the best fuels and technologies to serve their communities. It also comes at a time when there are a growing number of technology choices, incentives and pressures on transit fleets to procure technology to meet local clean air, energy and climate objectives.

The new clean diesel bus technology of today is the result of an interconnected system of clean fuels, advanced engine design and exhaust or aftertreatment technologies working together to reduce emissions to near-zero emissions. New clean diesel buses have reduced both NOx and particulate matter emissions by 98% compared to 1988 buses.—Ezra Finkin
Share of fuels and engines in the public transit bus fleet in 2013 according to APTA. Of the diesel buses currently in the US fleet, Finkin said APTA’s data showed that 81% were conventional diesels, 12% were diesel-electric, and 7% operated on biodiesel. Click to enlarge.

DSM launches next-gen Diablo high-temperature-resistant polyamides for engine compartment applications

Sat, 2014-10-18 10:57

Royal DSM is launching its next generation of Diablo high-temperature-resistant polyamides. The new grades are part of both DSM’s Stanyl polyamide 46 and Akulon 6/66 portfolios and are aimed at applications in automotive engine compartments where temperatures can reach as high as 260 ˚C (500 ˚F).

The automotive industry’s constant drive to create more fuel-efficient designs has resulted in reduced space and higher temperatures under the hood, due in part to the inclusion of new features such as improved pedestrian impact protection and the increasing use of turbochargers and superchargers. DSM’s next-generation Diablo grades can help manufacturers by providing both long-term and short-term heat resistance.

The technology provides a significant improvement in long-term temperature resistance components such as air intake manifolds with integrated intercoolers, ducts, charge air cooler end caps, mixing tubes and resonators used in the latest car engines.

The latest version of Stanyl Diablo polyamide 46 is able to withstand a continuous use temperature of 230 °C (446 ˚F), while the new Akulon Diablo withstands a 220 °C (428 ˚F) continuous-use temperature. Both new grades have improved resistance to short-term high temperature peaks as measured by deflection temperature under load (HDT).

New Stanyl Diablo has an improved HDT of 267 °C (513 ˚F), while the new Akulon Diablo has an HDT of 245 °C (473 ˚F). The long-term heat aging and the HDT of the new materials are evidence of their superior characteristics compared to competing materials currently on the market, DSM says.

The new grades also have improved resistance to chemicals and gases in EGR (exhaust gas recirculation) systems. They have very good processing properties and create finished parts with high-burst pressure-weld-line strength as well as excellent surface finish.

Lawrence Livermore graphene aerogels could improve performance of carbon-based superconductors by more than 100%

Sat, 2014-10-18 07:25

Researchers at Lawrence Livermore National Laboratory (LLNL) are developing modified graphene aerogels for application in supercapacitor electrodes. LLNL’s graphene aerogel material could potentially improve on the performance of commercial carbon-based supercapacitors by more than 100%, said LLNL’s Dr. Patrick Campbell, lead author of a paper on the technology published in the RSC journal Journal of Materials Chemistry A.

In the paper, the LLNL team reports a 2.9-fold increase in electrical energy storage capacity (up to 23 Wh kg−1) of their graphene materials by modifying them with anthraquinone. These hybrid electrodes demonstrate battery-like energy density, supercapacitor-like power performance, and superb long-term stability, the researchers said.

Binder-free, monolithic, high surface area graphene macro-assemblies (GMAs) are promising materials for supercapacitor electrodes, but, like all graphitic carbon based supercapacitor electrodes, still lack sufficient energy density for demanding practical applications. Here, we demonstrate that the energy storage capacity of GMAs can be increased nearly 3-fold (up to 23 Wh kg−1) by facile, non-covalent surface modification with anthraquinone (AQ). AQ provides battery-like redox charge storage (927 C g−1) without affecting the conductivity and capacitance of the GMA support.

The resulting AQ-GMA battery/supercapacitor hybrid electrodes demonstrate excellent power performance, show remarkable long-term cycling stability and, by virtue of their excellent mechanical properties, allow for further increases in volumetric energy density by mechanical compression of the treated electrode. Our measured capacity is very close to the theoretical maximum obtained using detailed density functional theory calculations, suggesting nearly all incorporated AQ is made available for charge storage.—Campbell et al.

Compared to traditional carbon-based supercapacitor electrodes fabricated from carbon black and binder materials, graphene aerogels offer many advantages such as control of density and pore size distribution, and increased conductivity due to carbon linkers between the active carbon sheets and the absence of binder materials.

Aerogels derived from carbon as well as inorganic materials were developed at LLNL and have found a number of applications—from capturing space dust to lining the inside of National Ignition Facility targets.

Graphene aerogels are a relatively new type of aerogel that are ideal for energy storage applications because of their extremely high surface area, excellent mechanical properties and very high electrical conductivity. We have been exploring various ways to enhance their energy storage properties such as increasing electrode density through mechanical compression. The non-covalent modification strategy is simply another route to increase the electrical energy storage capacity.—Patrick Campbell

Other Livermore researchers involved in the project include Brandon Wood, Marcus Worsley and Ted Baumann.

The research was funded by the Department of Energy Office of Energy Efficiency and Renewable Energy and the LLNL Laboratory Directed Research and Development Program.

Resources

  • P. G. Campbell, M. D. Merrill, B. C. Wood, E. Montalvo, M. A. Worsley, T. F. Baumann and J. Biener (2014) “Battery/supercapacitor hybrid via non-covalent functionalization of graphene macro-assemblies,” J. Mater. Chem. A 2, 17764-17770 doi: 10.1039/C4TA03605K

Graphene NanoChem and Sync R&D partner to develop graphene-enhanced Li-ion battery for shuttle bus in Malaysia

Sat, 2014-10-18 06:24

Malaysia-based Graphene NanoChem’s wholly-owned subsidiary Platinum Nanochem Sdn Bhd has entered into a product development and collaboration agreement with Sync R&D Sdn Bhd jointly to develop a graphene-enhanced lithium-ion battery solution for electric buses under the Electric Bus 1 Malaysia program (EB1M Program).

The partners will develop and integrate a graphene-enhanced Li-on battery into a prototype electric shuttle bus in Malaysia designed and developed by Sync R&D, with Graphene NanoChem taking the lead role in the applications development activities to design and produce the battery.

Under the Malaysian Economic Transformation Program, the Government has announced its aim to accelerate the Electric Vehicles policy and regulations for public and private transportation, targeting 2,000 electric buses and 100,000 electric cars on the road by 2020.

The 2015 Malaysian Budget, announced in October 2014, set the target to introduce 50 electric buses initially, with the first anticipated in early 2015. A critical component to this initiative is the development of the infrastructure to enable electric vehicle component manufacturing in Malaysia, including for Li-on Battery technology and manufacturing.

A prototype of the graphene-enhanced Li-on battery is expected to be completed in 2016.

arbcombo -- Public Workshop on FY 2015-16 AQIP Funding Plan and GGRF Low-Carbon Transportation Investments

Fri, 2014-10-17 20:34
The Air Resources Board (ARB or Board) invites you to participate in a public kickoff workshop to begin developing the Fiscal Year (FY) 2015-16 Funding Plan for the Air Quality Improvement Program (AQIP) and Low Carbon Transportation Greenhouse Gas Reduction Fund (GGRF) Investments.

Nissan leads with transfer of California ZEV credits out for year ending 30 Sep 2014

Fri, 2014-10-17 18:40

Nissan led with California ZEV credit transfers out during the last report period. Click to enlarge.

Between 1 October 2013 and 30 September 2014, Nissan transferred out 663.6 ZEV (zero emission vehicle) credits from its balance account, according to the latest report by the California Air Resources Board (ARB)—just edging out Tesla with 650.195 credits. The next closest was Fiat, with 235.2 ZEV credits transferred out; followed by Ford with 38.738.

This latest credit balance report reflects ZEV regulation compliance through model year 2013, representing a total of 3.5 million vehicles including: more than 500 fuel cell vehicles; 38,000 battery electric vehicles; 29,300 neighborhood electric vehicles (NEVs); 30,000 plug-in hybrids; 570,000 hybrids; and 3 million gasoline vehicles. As of September 2014, more than 100,000 ZEVs and plug-in hybrids are on California roads.


ZEV credit transfers in. Click to enlarge.

Mercedes-Benz was the leading automaker for acquiring ZEV credits (transfer in), followed by Honda. Chrysler was third (almost the same transferred in as Fiat transferred out: 237.804 in, with Fiat transferring out 235.2).

The latest data show a very different picture from the prior year’s report, when electric vehicle manufacturer Tesla Motors transferred out 1,311.520 ZEV credits, by far, the largest of any automaker in the state. (Earlier post.)


ZEV credit balances by vehicle type as of 30 September 2014. In complying with the ZEV Regulation, manufacturers operate vehicles in California which generate varying credits based on vehicle type.

ZEV = Zero Emission Vehicle, e.g. fuel cell or battery electric
NEV = Neighborhood Electric Vehicle
TZEV = Transitional Zero Emission Vehicle, e.g. a plug-in hybrid
AT PZEV = Advanced Technology Partial Zero Emission Vehicle, e.g. a non-plug-in hybrid
PZEV = Partial Zero Emission Vehicle, e.g. low emission combustion engined vehicle

There are also other parties generating credits that do not have ZEV requirements. Click to enlarge.

The California ZEV Regulation requires large volume and intermediate volume vehicle manufacturers (LVMs and IVMs) to bring to and to operate in California a certain percentage of ZEVs (such as battery-electric and fuel-cell vehicles); plug-in hybrids; hybrids; and gasoline vehicles with near-zero tailpipe emissions.

Why NMOG? Under ZEV accounting, credits earned are multiplied by the g/mile NMOG fleet average requirement for the appropriate model year. In the ZEV Regulation, g/mi NMOG is used only as index (which decreases over time)—i.e.,it is the “currency” in which credits are stored in and does not represent actual values of g/mi NMOG. The intent of this multiplier was to reward early production of vehicles.

Large volume manufacturers for the 2013 model year included the big six: Chrysler, Ford, GM, Honda, Nissan and Toyota. IVMs in 2013 were BMW, Hyundai, Kia, Land Rover, Mazda, Mercedes Benz, Subaru and Volkswagen.

A vehicle manufacturer’s ZEV requirement is based on a percentage of all passenger cars and light-duty trucks from 0 to 8,500 lbs (3,856 kg), delivered for sale in California.

Positive credit balances represent a successful over-compliance with the ZEV Regulation. Manufacturers can use these balances to provide flexibility in the timing and production of bringing new clean cars to the market to meet the ZEV requirements in coming years. Manufacturers may also transfer credits between manufacturers and third parties.

newsclips -- ARB Newsclips for October 17, 2014.

Fri, 2014-10-17 18:37
ARB Newsclips for October 17, 2014.

zev-program -- 2013 Zero emission vehicle (ZEV) regulation data publicly available

Fri, 2014-10-17 15:29
The Air Resources Board (ARB) is providing ZEV Regulation information on 2013 vehicle manufacturer volume status, 2013 California vehicle production of large and intermediate volume manufacturers, ZEV credit balances and ZEV credit transfers as of September 30, 2014.

MIT/Stanford team refines TREC battery for harvesting low-grade waste heat

Fri, 2014-10-17 13:17

In May, researchers at MIT and Stanford University reported the development of new battery technology for the conversion of low-temperature waste heat into electricity in cases where temperature differences are less than 100 ˚Celsius. The thermally regenerative electrochemical cycle (TREC) uses the dependence of electrode potential on temperature to construct a thermodynamic cycle for direct heat-to-electricity conversion. By varying the temperature, an electrochemical cell is charged at a lower voltage than discharged; thus, thermal energy is converted to electricity. (Earlier post.)

Now, in a paper in the ACS journal Nano Letters, the team reports a refinement of the earlier Prussian blue analog-based system system, which although it operated with high efficiency, used an ion-selective membrane which, in turn, raised concerns about the overall cost. The refined system is a membrane-free battery with a nickel hexacyanoferrate (NiHCF) cathode and a silver/silver chloride anode. When the battery is discharged at 15 °C and recharged at 55 °C, thermal-to-electricity conversion efficiencies of 2.6% and 3.5% are achieved with assumed heat recuperation of 50% and 70%, respectively.

A vast amount of low-grade heat (<100 °C) exists in industrial processes, the environment, biological entities, and solar-thermal and geothermal energy. Conversion of this low-grade heat to electricity is difficult due to the distributed nature of these heat sources and the low temperature differential. Different technologies, such as solid-state thermoelectric energy conversion and organic Rankine cycles, are being actively investigated but face their own challenges in energy conversion efficiency, cost, and system complexity. Thermally regenerative electrochemical cycle (TREC) is an alternative approach based on the temperature dependence of cell voltage of electrochemical systems.—Yang et al.

TREC entails a four-step process:

  1. heating up the cell with waste heat;
  2. charging at the higher temperature;
  3. cooling down the cell; and
  4. discharging at low temperature.

Because the charging voltage is lower at high temperatures than at low temperatures, once the battery has cooled it delivers more electricity than what was used to charge it—i.e., converting heat to electricity.

The concept of TREC was developed a few decades ago, the researchers note, but focused on high-temperature applications (500−1500 °C) and showed efficiencies up to 40−50% of the Carnot limit. Low-temperature TREC did not received as much attention since electrode materials with low polarization and high charge capacity at low temperature were limited.

The low-temperature TREC system on which the research team earlier reported was based on a copper hexacyanoferrate (CuHCF) cathode and a Cu/Cu2+ anode. The low polarization of electrodes, moderate temperature coefficient, high charge capacity, and low heat capacity led to a high efficiency of 5.7% when the cell was operated between 10 and 60 °C, assuming a heat recuperation efficiency of 50%.


Schematic of thermally regenerative electrochemical cycle (TREC). (a) The voltage−capacity plot of a TREC. Net energy is generated because the discharge voltage is higher than charge voltage. (b) The corresponding temperature−entropy (T− S) plot. (c) A TREC with an ion-selective membrane to block certain ions to avoid side reactions (i.e., the earlier system). (d) The new membrane-free NiHCF/Ag/AgCl system with no unwanted reaction between electrodes and ions. Credit: ACS, Yang et al. Click to enlarge.

However, one potential issue they identified with their system was the use of an ion-selective membrane to allow NO3− anion passing through but not Cu2+ cations to avoid side reaction between CuHCF and Cu2+. Ion-selective membranes are currently expensive; further, it would be difficult to block completely the penetration of Cu2+ in long-term operation. A membrane-free systems would lower the cost and facilitate long-term operation, making the TREC battery more practical, they concluded.

To address this issue, we apply a criterion that any soluble chemical species in electrolyte should not induce adverse side reactions other than the desired two half-cell reactions. In this paper, a membraneless electrochemical system with a nickel hexacyanoferrate (NiHCF, KNiIIFeIII(CN)6) cathode and a silver/silver chloride anode is demonstrated, where no adverse side reaction is introduced due to solutes in electrolyte. … In this system, ions involved in each electrode do not have side reactions with each other, so the ion-selective membrane is unnecessary and can be replaced by an inexpensive porous separator.

…We believe that further optimization and searching for new systems will lead to new development and possibly practical deployment of TREC.—Yang et al.

Resources

  • Yuan Yang, James Loomis, Hadi Ghasemi, Seok Woo Lee, Yi Jenny Wang, Yi Cui, and Gang Chen (2014) “Membrane-Free Battery for Harvesting Low-Grade Thermal Energy” Nano Letters doi: 10.1021/nl5032106

Abengoa opens cellulosic ethanol plant in Hugoton; 1st commercial deployment of Abengoa enzymatic hydrolysis

Fri, 2014-10-17 10:17

The Hugoton cellulosic ethanol plant covers 400 acres, more than 380 of which will be used to store biomass from local farmers. Click to enlarge.

Abengoa held the grand opening of its cellulosic ethanol plant in Hugoton, Kansas, located about 90 miles (145 km) southwest of Dodge City. Abengoa’s new biorefinery finished construction in mid-August and began producing cellulosic ethanol at the end of September with the capacity to produce up to 25 million gallons (94.6 million liters) per year. Abengoa received a $132.4-million loan guarantee and a $97-million grant through the Department of Energy to support construction of the Hugoton facility.

The plant utilizes only “second generation” (2G) biomass feedstocks for ethanol production—i.e.non-edible agricultural crop residues (such as stalks and leaves) that do not compete with food or feed grain. The facility also features an electricity cogeneration component allowing it to operate as a self-sufficient renewable energy producer. By utilizing residual biomass solids from the ethanol conversion process, the plant generates 21 megawatts (MW) of electricity—enough to power itself and provide excess clean renewable power to the local Stevens County community.

The Hugoton plant opening also marks the first commercial deployment of Abengoa’s proprietary enzymatic hydrolysis technology, which turns biomass into fermentable sugars that are then converted to ethanol. (Abengoa Bioenergy licensed from Dyadic the use and modification of a microorganism that produces the enzymes required for the conversion of cellulose into sugars.)

In addition to the plant’s crucial role in proving the commercial viability of cellulosic ethanol, its success provides a platform for Abengoa’s future development of other bioproducts that reduce petroleum use, such as bioplastics, biochemicals and drop-in jet fuel.

The Hugoton plant opening is the result of 10 years of technical development, roughly 40,000 hours of pilot and demonstration plant operation, and the support of the DOE. This is a proud and pivotal moment for Abengoa and for the larger advanced bioenergy industry—and further demonstrates our longstanding commitment to providing sustainable energy alternatives in the United States. This would have been simply impossible without the establishment of the Renewal Fuel Standard.— Manuel Sanchez Ortega, CEO of Abengoa

At full capacity, the Hugoton facility will process 1,000 tons per day of biomass, most of which is harvested within a 50-mile radius each year—providing $17 million per year of extra income for local farmers whose agricultural waste would otherwise have little or no value.

Of that biomass, more than 80% is expected to consist of irrigated corn stover, with the remainder comprised of wheat straw, milo stubble and switchgrass.

Abengoa plans to offer licenses and contracts to interested parties covering every aspect of this new industry—from process design, to engineering, procurement and construction (EPC), supply of exclusive enzymes, as well as operations and marketing of the completed products from the facility.

The proprietary enzymatic hydrolysis technology utilized commercially at Hugoton is a focal point in Abengoa’s efforts to diversify the range of raw material feedstocks from which biofuels and bioproducts can be produced. For example, for more than a year the company has been operating a demonstration-scale facility that is capitalizing on the same technology and enzyme cocktail used at Hugoton to extract cellulosic sugars from municipal solid waste (trash), thereby allowing expansion of the renewable fuels industry from rural to urban areas.

With a biofuels presence on three continents, Abengoa is an international biotechnology company—one of the largest ethanol producers in the United States and Brazil, and the largest producer in Europe with a total of 867 million gallons (3.3 billion liters) of annual installed production capacity distributed among 15 commercial-scale plants in five countries.

Abengoa’s overall presence in the United States—including its solar, water desalination, biofuels and engineering and construction businesses—has grown exponentially since the company expanded its business more than a decade ago. Some 26% of the company’s assets are currently in the United States, which is Abengoa’s largest market in terms of sales.

SAE International publishes revised SAE J2880 standard for recommended Green Racing protocols

Fri, 2014-10-17 07:00

SAE International has published the revised J2880_201406 Standard, superseding the older J2880_200810 Standard. The Department of Energy (DOE), Environmental Protection Agency (EPA), and SAE International, along with partners and representatives from the motorsports industry, developed these protocols to be used by those automotive racing series who seek recognition as a Green Racing Series.

The Recommended Green Racing Protocols establish guidelines enabling motorsports competition to further develop technologies and fuels that respond to the current and future needs of on road vehicles, while they provide a sustainable future for motorsports worldwide. SAE J2880 aligns motorsports with evolving transportation demands, to promote and improve energy efficiency and diversity, and demonstrate environmental responsibility while supporting motorsport that is entertaining, exciting, cost effective and safe.

The SAE J2880:

  • Provides sanctioning bodies with recommendations to help them align competition rules with the objectives of sustainable transportation;

  • Supports environmentally responsible and sustainable technology that is transferable to production vehicles;

  • Promotes environmentally friendly operations of motorsports venues, competition events, and racing team facilities; and

  • Assists sanctioning bodies in the establishing a roadmap to increase green initiatives.

The elements of J2880 identify a range of technologies, fuels and operational procedures that support development of a sustainable future for both motorsports and personal mobility, and organizes them into a matrix of five Green Racing elements and four levels of commitment within each element. These elements are:

  • Propulsion systems
  • Fuel/Energy Carriers
  • Energy Recovery
  • Improved Efficiency
  • Emission Reduction

Within each element there are four possible levels of commitment, i.e., Core, Enhanced, Elevated, and Pinnacle, which is the highest level of Green Racing commitment.

Since 2008, The International Motor Sports Association (IMSA), in a partnership with, EPA, DOE, and SAE, promote the development and use of alternative technologies and renewable fuels in the motorsports industry.

Shanghai GM to be first automaker to introduce 4G LTE service in China

Fri, 2014-10-17 06:00

Shanghai General Motors will become the first automaker in China to offer embedded 4G LTE services in its vehicles. The first Shanghai GM offering to be equipped with OnStar 4G LTE will be a Cadillac model in 2015.

The high-speed data service is made possible by a new OnStar 4G LTE connection in the vehicle. Deployment of OnStar 4G LTE connectivity technology will provide improved OnStar safety and security services and new features such as a built-in Wi-Fi hotspot. It will be the most comprehensive in-vehicle safety and connectivity system available in China, the company said. Shanghai GM expects to announce its 4G LTE carrier partner in the coming months.

The built-in OnStar 4G LTE system is specifically designed for in-vehicle use, as it is integrated into the vehicle’s electrical system and includes an external antenna to maximize coverage and connectivity. Customers will not be required to have a smartphone to use connected services.

Existing OnStar services include Automatic Crash Response, Turn-by-Turn Navigation and On-Demand Diagnostics. A 4G LTE connection enhances the speed and performance of these services, in addition to introducing new features such as Wi-Fi.

With mobile data speeds up to 10 times faster than today’s speeds, increased responsiveness, and the ability to support simultaneous voice and data connections, a built-in 4G LTE connection will enable advances in a wide range of in-vehicle communication and entertainment capabilities.

GM has made a global commitment to embed OnStar 4G LTE technology in millions of vehicles across its brands around the world, starting with the US and Canada in 2014, and Europe and China in 2015. GM says that no other automaker is putting the technology into as many vehicles in as many segments.

The pairing of OnStar with high-speed mobile broadband will serve as a platform for future innovations in traffic, safety and customer care.

Siemens integrates EV motor and inverter in single housing; common cooling and SKiN

Fri, 2014-10-17 06:00

Siemens has developed a solution for integrating an electric car's motor and inverter in a single housing. Click to enlarge.

Siemens has developed a solution for integrating an electric car’s motor and inverter in a single housing. The motor and the inverter, part of the power electronics which converts the battery’s direct current into alternating current for the motor, have up to now been two separate components. The new integrated drive unit saves space, reduces weight, and cuts costs.

The solution’s key feature is the use of a common cooling system for both components. This ensures that the inverter’s power electronics don’t get too hot despite their proximity to the electric motor, and so prevents any reduction in output or service life.

Because range is a decisive criterion for purchasing an electric car, automakers are always striving to reduce vehicle weight. This was also the aim of the Siemens engineers. Their idea was to integrate the inverter into the motor, as this would reduce weight because only a single housing would be needed.

In addition, it would create six to seven liters of additional installation space, which could be used for a charging unit, for example. Integration would also eliminate the costs of wiring the motor to the inverter and fewer assembly steps would be needed to produce the vehicle.

Siemens developed the integrated drive unit—Sivetec MSA 3300—on the basis of a series electric motor. The engineers adapted the housing in such a way that the inverter could be integrated into the motor.

One problem they faced was the heat generated by the electric motor. At high temperatures, the output of the IGBT modules—the high-performance semiconductors that convert the battery’s current into alternating current—has to be limited. For this reason, inverters in electric cars always have their own cooling system.

A key feature of the integrated drive unit was therefore the creation of a special cooling water system around the motor and inverter. The coolest water first flows around very thermally sensitive components such as the IGBT modules and the intermediate circuit capacitor, after which it is led into the motor’s cooling jacket.

The water flow system is designed in such a way that a kind of water screen is created between the inverter electronics and the motor. As a result, it thermally isolates the two units from one another.

Another component of the overall solution is the very robust power modules featuring SkiN technology. Introduced in 2011 by power electronics leader Semikron, SKiN technology comprises the consistent application of sintering technology on all material combinations significant to load-cycling in a power module—i.e., sintered compositions replace all soldering and bond connections. When thermal load fluctuates, the electrical contact between the chip and the bonding wire is a weak point of semiconductor components.

(Siemens began collaborating more closely with Semikron on automotive power electronics in 2013, and took over Semikron subsidiary VePOINT. VePOINT developed power electronic components and systems, based on Semikron SKiN technology, specifically for the hybrid and electric vehicle market. (Earlier post.)

SKiN flex layers allow an increase of about 25% surge current in the power module due to the sintered layer on the chip tops. Compared to conventional power modules, the additional performance allows an approximate doubling of the current density. Excellent thermal and electrical properties of the sintered layers increase the module lifetime up to tenfold, Semikron says.

If, in addition, the DCB substrate is sintered directly onto the heatsink, the thermal resistance to the heatsink is reduced drastically over traditional interface materials—such as thermal pastes or foils. This decreases the thermal resistance Rth[j-a] between the semiconductor chip and coolant by up 30%, which enables a power increase or a reduction in volume by up to 35%.



Top: Comparison of standard connection technology (solder/bonding) and SKiN technology. SkiN is a bonding technology that connects the surface of the semiconductor chip without requiring bonding wire. When the thermal load fluctuates, the electrical contact between the chip and the bonding wire is a weak point of semiconductor components.

Bottom: Comparison of the partial thermal transfer resistances in a standard module and a SKiN power module with sintered heatsink. Click to enlarge.

The integrated motor/inverter concept’s feasibility has already been demonstrated in a lab under the typical load curves and operating conditions of an electric motor in an automobile. Siemens said that the industry has expressed interest in Sivetec MSA 3300, and the system was recently nominated for the eCarTec Award 2014, which is the Bavarian State Award for Electric and Hybrid Mobility.

11 more GM facilities worldwide go landfill-free; total up to 122

Fri, 2014-10-17 05:11

Eleven more General Motors facilities have achieved landfill-free status. The running total is 122 manufacturing and non-manufacturing operations spanning Asia, Europe, and South and North America that recycle, reuse or convert to energy all waste from daily operations.

GM’s new landfill-free facilities include:

  • CAMI Assembly (Canada)
  • Colmotores Assembly (Colombia)
  • Joinville Engine (Brazil)
  • Zaragoza Assembly (Spain)
  • Zaragoza Stamping (Spain)
  • Grand Rapids Operations (Michigan)
  • Burton Warehouse and Distribution Center (Michigan)
  • GM Heritage Center (Michigan)
  • Shanghai Headquarters (China)
  • Luton Warehouse (England)
  • Fontana Warehouse and Distribution Center (California)

The addition of these 11 facilities to landfill-free status helps GM avoid more than 600,000 metric tons of CO2-equivalent emissions. This is comparable to the greenhouse gas benefit of 15 million tree seedlings grown for 10 years.

Employee awareness is key in the drive to landfill-free. Colmotores Assembly in Colombia launched awareness campaigns that engaged employees in reducing waste and sorting it correctly. GM’s Shanghai headquarters, a LEED-Gold facility, formed a “Green Team” spanning IT, finance, facilities, R&D and supply chain departments to identify recycling and waste reduction opportunities. Luton Warehouse attributes its success to a robust training initiative that drove a zero-waste culture.

All of these facilities treat their waste as resources out of place and employ a number of methods to give them a second or third life.

  • Reduce: Zaragoza Assembly changed its manufacturing process to reduce solvent consumption from its paint shop; it now reuses 80 percent of it. Packaging continues to be a large waste stream for many plants and CAMI Assembly is tackling it by setting aggressive targets to reduce non-reusable packaging.

  • Reuse: Grand Rapids Operations’ in-house oil recycling saves GM $1.2 million per year. It recycles and reuses every gallon of oil it buys from a refinery several times.

  • Recycle: CAMI Assembly turns scrap wood into mulch for its wetlands and Grand Rapids Operations recycles grinding wheels as sandpaper. The Grand Rapids site also works with a partner that processes wastewater treatment sludge into a fuel source for the building materials industry.

  • Compost: Zaragoza composts wastewater treatment sludge to create fertilizer and Joinville Engine composts its organic cafeteria waste to provide additional nutrients for the site’s trees and plants.

A strong network of recycling partners and suppliers helps facilities achieve their goals. Localizing the supply chain strengthens the business case and reduces overall carbon footprint. One of Zaragoza’s biggest challenges was finding a nearby partner to efficiently transport and treat paint sludge so it could be used to generate electricity. Burton Warehouse and Distribution Center hired a waste technician to help sort packaging waste generated from expanded shipping and distribution operations. A new recycling partner helped push GM’s Heritage Center to landfill-free status.

GM’s goal is to achieve 125 landfill-free sites globally by 2020. The company already has met its 10% total waste reduction commitment seven years ahead of schedule.

GM was named a Michigan Green Leader and Green Corporate Citizen for its landfill-free program, and received a Top Project of the Year Award from Environmental Leader for driving a global movement for zero waste. GM was one of the first companies—and the only automaker—inducted into the USEPA WasteWise Hall of Fame.

New WSU palladium-iron catalyst could improve drop-in biofuels production from pyrolysis oils

Fri, 2014-10-17 05:00


The addition of palladium (Pd) prevents deactivation (addition of oxygen, red spheres) of an iron catalyst in the reaction that removes oxygen from biofuel feedstock. Credit: ACS, Hensley et al.. Click to enlarge.

Washington State University researchers have developed a new palladium-iron hydrodeoxygenation catalyst (Pd/Fe2O3) that could lead to making drop-in biofuels cheaply and more efficiently. Their work is described in two papers in the October issue of the journal ACS Catalysis and is featured on the cover.

The first WSU paper (Hong et.al) describes the synthesis of a series of Pd/Fe2O3 catalysts and their performance for the hydrodeoxygenation of m-cresol—a phenolic compounds used as a model compound in the HDO research, as it can be derived from pyrolysis of lignin. The second (Hensley et al.) reports on a combined experimental and theoretical approach to understand the potential function of the surface Pd in the reduction of Pd/Fe2O3.

One method of producing biofuels is through the pyrolysis of biomass to bio-oils and successive refinery of bio-oils, and this process has been identified as the most cost-effective approach. The key issue in the bio-oil upgrading is to efficiently reduce their high oxygen content (∼20−40 wt %) to less than 2 wt % for fuel applications. The oxygenates in bio-oils mainly exist in the form of acetic acid, furans, ketones, and phenolics, which are corrosive, thermally unstable, and highly viscous. The removal of oxygen in these bio-oils can be achieved in a similar manner with the hydrodesulfurization (HDS) and hydrodenitrogenation (HDN) processes in petroleum industry, i.e., removing oxygen in the form of water in hydrodeoxygenation (HDO) process.—Hensley et al.

These catalysts need to be fast and efficient. The WSU study shows how a two-metal approach could improve the catalyst and minimize the amount of hydrogen needed, along with the associated costs.

Iron catalysts have been an inexpensive way to remove oxygen from plant-based materials; however, the catalyst can stop working when it interacts with water, which is a necessary part of biofuels production. The iron rusts. Palladium can work in water, but it is not terrific at removing oxygen; and the metal is very expensive.

Led by Voiland Distinguished Professor Yong Wang, who holds a joint appointment at Pacific Northwest National Laboratory (PNNL) as an associate director at the Institute for Integrated Catalysis, the researchers developed a mixture of the two metals, iron along with a tiny amount of palladium, to serve as a catalyst to efficiently and cheaply remove oxygen.

The synergy between the palladium and the iron is incredible. When combined, the catalyst is far better than the metals alone in terms of activity, stability and selectivity.—Prof. Yong Wang
Mechanism of Pd−Fe Synergy in HDO of m-Cresol. H2 preferentially adsorbs and dissociates on the Pd attached to the Fe surface, followed by spillover to the metallic Fe sites where the substrate, m-cresol, adsorbs and activates.
The adsorption mode of m-cresol on the iron surface enables the high selectivity toward direct HDO products—i.e., toluene, benzene, and xylene. Meanwhile, Pd is the active site for activating hydrogen and maintains the high hydrogen coverage on the metallic Fe surface.

Once the product forms via surface reaction on Fe, it readily desorbs to complete the catalytic cycle without further reaction. The surface enrichment of active hydrogen also efficiently removes the oxygen on the surface and thus suppresses the reoxidation of the active Fe under the reaction conditions. Credit: ACS, Hong et al. Click to enlarge.

Adding extremely small amounts of palladium to iron helped cover the iron surface of the catalyst with hydrogen, which caused the reaction to speed up and work better. It also prevented water from interrupting the reactions; further, less hydrogen was needed to remove the oxygen.

With biofuels, you need to remove as much oxygen as possible to gain energy density. Of course, in the process, you want to minimize the costs of oxygen removal. In this case, you minimize hydrogen consumption, increase the overall activity and gain high yields of the desired fuel products using much less expensive and more abundant catalyst materials.—Yong Wang

The team used advanced techniques—including high-resolution transmission electron microscopy, X-ray photoelectron spectroscopy and extended X-ray absorption fine structure spectroscopy—to understand how atoms on the catalyst’s surface interact with the plant material lignin. Corresponding theoretical calculations were done by a WSU team led by Jean-Sabin McEwen.

The team is now designing catalysts to work under wetter conditions to better approach realistic conditions rather than just using model compounds.

Resources

  • Yongchun Hong, He Zhang, Junming Sun, Karim M. Ayman, Alyssa J. R. Hensley, Meng Gu, Mark H. Engelhard, Jean-Sabin McEwen, and Yong Wang (2014) “Synergistic Catalysis between Pd and Fe in Gas Phase Hydrodeoxygenation of m-Cresol” ACS Catalysis 4 (10), 3335-3345 doi: 10.1021/cs500578g

  • Alyssa J. R. Hensley, Yongchun Hong, Renqin Zhang, He Zhang, Junming Sun, Yong Wang, and Jean-Sabin McEwen (2014) “Enhanced Fe2O3 Reducibility via Surface Modification with Pd: Characterizing the Synergy within Pd/Fe Catalysts for Hydrodeoxygenation Reactions” ACS Catalysis 4 (10), 3381-3392 doi: 10.1021/cs500565e

workshops -- New Workshop(s) posted to ARB's website

Thu, 2014-10-16 22:00
One or more workshops/meetings have been scheduled and are now located in ARB's Workshop Calendar.

arbcombo -- Public Workshop for the Low Carbon Fuel Standard Compliance Scenarios and Cost Containment

Thu, 2014-10-16 20:23
The California Air Resources Board (ARB) staff invites you to participate in a Low Carbon Fuel Standard (LCFS) public workshop on Monday, October 27, 2014.

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