[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.]
UC Riverside researchers find mixed emissions impact from use of higher ethanol and butanol fuels in FFVs
November 24, 2014
A study by University of California, Riverside researchers found that the use of higher ethanol blends and a 55% butanol blend in port-fueled and direct injection flexible fuel vehicles (FFVs) could lead to emission changes of GHGs, CO, aldehydes, BTEX (monoaromatic hydrocarbons of benzene, ethylbenzene, toluene, m/p-xylene, and o-xylene), and particulates.
In a paper in the ACS journal Environmental Science & Technology, they reported that the higher alcohol fuels would decrease PM mass and number emissions, although current technology direct injection fueling produces higher particle number and soot mass emissions than the PFI fueling as a result of liquid fuel wetting effects and insufficient air fuel mixing. Particulate emissions were clearly influenced by certain fuel parameters including oxygen content, hydrogen content, and aromatics content.
UCLA researchers develop synthetic biocatalytic pathway for more efficient conversion of methanol to longer-chain fuels
November 18, 2014
Researchers at the UCLA Henry Samueli School of Engineering and Applied Science led by Dr. James Liao have developed a more efficient way to turn methanol into useful chemicals, such as liquid fuels, and that would also reduce carbon dioxide emissions. The UCLA team constructed a synthetic biocatalytic pathway that efficiently converts methanol under room temperature and ambient atmospheric pressures to higher-chain alcohols or other higher carbon compounds without carbon loss or ATP expenditure.
Building off their previous work in creating a new synthetic metabolic pathway for breaking down glucose that could lead to a 50% increase in the production of biofuels (earlier post), the researchers modified the non-oxidative glycolysis pathway to utilize methanol instead of sugar. An open-access paper on the research was published in the 11 Nov. edition of the Proceedings of the National Academy of Sciences.
California Energy Commission to award up to $3M for advanced biofuel projects
October 28, 2014
The California Energy Commission’s Alternative and Renewable Fuel and Vehicle Technology Program (ARFVTP) announced (PON-14-602) the availability of up to $3 million in grant funds for biofuels projects that are in the early/pre-commercial technology development stage. This solicitation is emphasizing transformative technology solutions to significant biofuels industry problems that increase yields, productivity, or cost effectiveness of biofuel production; and/or that target a significant unmet need in California’s biofuels industry.
The ARFVTP has an annual budget of approximately $100 million and provides financial support for projects that increase the use of alternative and renewable fuels and advanced vehicle technologies.
Emissions study suggests E10 + renewable hydrocarbons a high bioenergy alternative for conventional cars
August 14, 2014
Researchers from VTT Technical Research Center of Finland and Neste Oil analyzed the exhaust emissions from three different spark ignition engine technologies—multipoint fuel injection (MPFI); direct-injection spark-ignition (DISI); and flex-fuel (FFV)—using different biofuels—low- and high-concentration ethanol blends; isobutanol; and biohydrocarbons. They report their findings in a paper in the ACS journal Environmental Science & Technology.
Among their conclusions was that the combination of ethanol or isobutanol with renewable hydrocarbon components (i.e., drop-in biohydrocarbons) could offer an option to achieve a high-bioenergy-content gasoline that is compatible with conventional gasoline-fueled cars (i.e., those limited to a 10% ethanol blend) without a significant change in emissions.
Cobalt and Andritz sign exclusive agreement for technology and engineering for production of cellulosic n-butanol
July 11, 2014
Cobalt Technologies, Inc. signed an exclusive global cooperation and supply agreement with Andritz Inc., the US subsidiary of international technology Group Andritz, to integrate Cobalt’s proprietary lignocellulosic pre-treatment process for the production of n-butanol with Andritz’s customized pre-treatment systems.
The primary alcohol n-butanol has traditionally been produced from fossil fuels. Engineered to achieve low production costs, Cobalt’s technology naturally converts both C5 and C6 sugars into bio-butanol, using any non-food lignocellulosic, renewable and sustainable feed-stock.
Synthetic biology company launches JV to commercialize gas-to-liquids bioconversion; isobutanol first target
March 28, 2014
Synthetic biology company Intrexon Corporation has formed Intrexon Energy Partners (IEP), a joint venture with a group of external investors, to optimize and to scale-up Intrexon’s gas-to-liquids (GTL) bioconversion platform. IEP’s first target product is isobutanol for gasoline blending.
Intrexon’s natural gas upgrading program is targeting the development of an engineered microbial cell line for industrial-scale bioconversion of natural gas to chemicals, lubricants and fuels, as opposed to employing standard chemical routes. Intrexon says it has already achieved initial proof of concept with an engineered microbial host converting methane into isobutanol in a laboratory-scale bioreactor.
Gevo transitioning Luverne plant to produce both isobutanol and ethanol; “side-by-side” configuration
March 26, 2014
Bio-isobutanol company Gevo, Inc. is transitioning its Luverne plant to the production of both isobutanol and ethanol. Gevo said that its decision—announced during its 4Q 2013 earnings call—to transition to the simultaneous production of both products is a direct result of (1) the steady progress made in executing its flexible production technology strategy and (2) the current high ethanol margin environment.
Producing both ethanol and isobutanol allows Gevo to fully utilize the Luverne plant and increase cash flow as Gevo continues to commercialize its isobutanol production capabilities.
Study finds butanol-gasoline blends effective to control soot from CI engines under Low Temperature Combustion
January 31, 2014
|(Left) Thermal efficiency and (right) soot from different gasoline-butanol blends at different EGR rates. Yang et al. Click to enlarge.|
A study by a team at Tianjin University found that the addition of n-butanol to gasoline for use in a compression ignition engine (CI) under Low Temperature Combustion (LTC) conditions has a significant effect on soot reduction. The peak soot value of a 30% butanol blend (B30) was 85% lower than that of pure gasoline; the EGR rate that corresponds to the peak value of soot is also decreased with the higher n-butanol fraction. Their study is published in the journal Fuel.
Partially Premixed Combustion involving the injection of gasoline fuel into CI engines is being explored by other researchers as a means to reducing simultaneously NOxand soot emissions. High octane fuels such as gasoline are preferred for high-efficiency and clean combustion at high engine loads, the Tianjin researchers note.
Oak Ridge Lab study finds E30 blend and EGR can deliver significant efficiency improvements in optimized SI engines
January 17, 2014
Researchers at Oak Ridge National Laboratory’s National Transportation Research Center (NTRC) report that an E30 (30% ethanol) mid-level ethanol blend shows promise as a means for significant improvement in vehicle efficiency in optimized spark-ignited (SI) engines. Results of the study by Derek Splitter and Jim Szybist suggest that it could be possible to implement a 40% downsize + downspeed configuration (1.2 L engine) into a representative midsize sedan using this combination of optimized engine and mid-level alcohol blend.
As an example, for a midsize sedan at a 65 mph (105 km/h) cruise, estimated fuel efficiency of 43.9 mpg (5.4 l/100 km) with engine-out CO2 of 102 g/km could be achieved with similar reserve power to a 2.0 L engine fueled with regular gasoline (38.6 mpg/6.1 l/100km, engine out CO2 of 135 g/km). The data suggest that, with midlevel alcohol–gasoline blends, engine and vehicle optimization can offset the reduced fuel energy content of alcohol–gasoline blends and likely reduce vehicle fuel consumption and tailpipe CO2 emissions.
US Army flies Black Hawk with 50:50 isobutanol-derived alcohol-to-jet fuel blend
December 23, 2013
Bio-isobutanol company Gevo, Inc. announced that the US Army has successfully flown the Sikorsky UH-60 Black Hawk helicopter on a 50:50 blend of Gevo’s ATJ-8 (Alcohol-to-Jet)—a renewable, drop-in alternative fuel for JP8 derived from isobutanol. (Earlier post.)
This flight marks the first Army Aircraft to fly on the isobutanol ATJ blend. (The US Air Force flew its first test flight using ATJ fuel in 2012. Earlier post.) The Army flight testing is being conducted at Aviation Flight Test Directorate (AFTD) on Redstone Arsenal, AL and is anticipated to be complete by March 2014.
NREL study probes emissions impact of butanol-gasoline blends in light-duty vehicles
November 26, 2013
|Summary of significant emissions results from the fuel testing. Credit: ACS, Ratcliff et al. Click to enlarge.|
Results of a study led by a team from the National Renewable Energy Laboratory on the impact of butanol-gasoline blends on light-duty vehicle emissions suggest that widespread deployment of n-butanol or i-butanol in the gasoline pool could result in changes to the estimated emissions of alcohols and carbonyls in the emissions inventory. Given equivalent deployment of butanols and ethanol, the results suggest emissions of unburned alcohols would decrease, but carbonyl emissions would increase; some of these compounds have poorly understood health effects, they note.
The carbonyls acetaldehyde and formaldehyde are classified as carcinogens or probable carcinogens by the National Institute for Occupational Safety and Health (NIOSH), International Agency for Research on Cancer, and the EPA. NIOSH considers butyraldehyde to have similar reactivity and mutagenicity to acetaldehyde.