[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.]
New catalysts convert ethanol to butanol with high selectivity; potential low-cost upgrade for ethanol plants
April 11, 2013
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.
Navigant forecasts global 6% CAGR for biofuels to 2023
March 29, 2013
|Total Biofuels production by fuel type, world markets: 2013-2023. Source: Navigant. Click to enlarge.|
Navigant Research forecasts global biofuels production will grow at a compound annual growth rate (CAGR) of 6% between 2013 and 2023, despite slower than expected development of advanced biofuels pathways (such as cellulosic biofuels); an expected expansion in unconventional oil production in key markets such as the United States; and a decline in global investment for biofuels in recent years.
In contrast, Navigant expects the CAGR for fossil-based gasoline, diesel, and jet fuel to be 3.1% over the forecast period. The research firm projects that total biofuels production will reach 62 billion gallons by 2023 or 5.9% of global transportation fuel production from fossil sources.
Study explores impact of alcohol-gasoline blends with early inlet valve closing at low and moderate loads on EGR tolerance
March 20, 2013
A team from Brunel University, MAHLE Powertrain and University College London studied the combined effects of different inlet valve operating strategies on combustion, performance and emissions with different ethanol and 1-butanol blends with gasoline in a single-cylinder spark-ignition research engine equipped with a fully variable valvetrain. Their paper is published in the journal Fuel.
The focus was to better quantify the effects of alcohol content and Early Inlet Valve Closing (EIVC) operation on EGR tolerance under the lowest speed-load conditions typically encountered (e.g., engine idle) while also quantifying the changes in optimum valvetrain settings at moderate speeds and loads where the effects of varying EGR tolerance were less dominant.
MIT team shows targeting metabolic pathways to mitochondria significantly boosts yeast production of isobutanol; potential for other chemicals as well
February 18, 2013
Researchers from MIT and the Whitehead Institute for Biomedical Research have devised a way to boost significantly isobutanol production in yeast by engineering isobutanol synthesis to take place entirely within mitochondria.
They showed that targeting metabolic pathways to mitochondria can increase production compared with overexpression of the enzymes involved in the same pathways in the cytoplasm. Compartmentalization of the Ehrlich pathway—a three-step catalytic breakdown of valine that produces isobutanol, earlier post—into mitochondria increased isobutanol production by 260%, whereas overexpression of the same pathway in the cytoplasm only improved yields by 10%, compared with a strain overproducing enzymes involved in only the first three steps of the biosynthetic pathway. A paper on their work is published in the journal Nature Biochemistry.
Researchers significantly boost yield of isobutanol from engineered yeast using new synthesis pathway located in the cytosol
November 06, 2012
A team at the Institute of Molecular Biosciences, Goethe-University Frankfurt led by Prof. Dr. Eckhard Boles, has developed a new synthesis pathway for engineering the industrial yeast Saccharomyces cerevisiae to improve the production of isobutanol via fermentation. The work, noted Boles, is being done for the Swiss biofuels and biochemical company Butalco, of which he is a co-founder. (Earlier post.)
In an open access paper published in the journal Biotechnology for Biofuels, the team reported achieving a titer of more than 630 mg/L isobutanol with a yield of nearly 15 mg/g glucose. The highest values reported before for recombinant S. cerevisiae were about 150 mg/L isobutanol and a yield of 6.6 mg/g glucose, they noted. Additional engineering should lead to even higher isobutanol production, they suggested.
Korean team uses systems metabolic engineering to enhance butanol production by C. acetobutylicum; reinforcing the “hot channel”
October 24, 2012
|Strategies for characterizing the complex butanol-forming routes by metabolic engineering coupled with system-level metabolic flux and mass balance analyses. Jang et al. Click to enlarge.|
Using a systems metabolic engineering approach, researchers in Korea have improved the butanol production performance of Clostridium acetobutylicum, one of the best known butanol-producing bacteria. A paper on their work is published in mBio, an open access journal issued by the American Society for Microbiology (ASM).
In addition, the downstream process was optimized and an in situ recovery process was integrated to achieve higher butanol titer, yield, and productivity. The combination of systems metabolic engineering and bioprocess optimization resulted in the development of a process capable of producing more than 585 g of butanol from 1.8 kg of glucose, which allows the production of biobutanol to be cost competitive, the researchers said.
MIT researchers modify soil bacterium for biosynthesis of isobutanol using carbon
August 21, 2012
Researchers at MIT have modified the soil bacterium Ralstonia eutropha to produce isobutanol and 3-methyl-1-butanol (branched-chain higher alcohols). These branched-chain higher alcohols can directly substitute for fossil-based fuels and be employed within the current infrastructure. The work is funded by the US Department of Energy’s Advanced Research Projects Agency – Energy (ARPA-E). (Earlier post.) A paper on their progress is published in the journal Applied Microbiology And Biotechnology.
When under nutrient stress and in the presence of excess carbon, wild-type Ralstonia eutropha H16 stops growing and begins producing polyhydroxybutyrate (PHB)—a complex carbon compound—as an intracellular carbon storage material during nutrient stress in the presence of excess carbon.
Cobalt Technologies and Rhodia to build bio n-butanol demonstration facility in Latin America
August 01, 2012
Cobalt Technologies, a developer of next-generation bio-based chemicals, and specialty chemical company Rhodia, member of the Solvay Group, will begin joint development and operation of a bio-butanol demonstration facility in Brazil. (Earlier post.) This is one more step by the two companies toward the construction of commercial-scale biorefineries using Cobalt’s technology to convert Brazilian bagasse and other local non-food feedstock into bio n-butanol in Latin America.
Under the Term Sheet, Cobalt and Rhodia will build and operate a biobutanol demonstration plant, which will validate Cobalt’s technology and its ability to seamlessly integrate with existing sugar mills in Brazil.
Gevo and Beta Renewables (Chemtex/TPG) to develop integrated process for cellulosic isobutanol
July 10, 2012
Gevo, Inc. signed a Joint Development Agreement (JDA) with Beta Renewables, a joint venture between Chemtex and TPG, to develop an integrated process for the production of bio-based isobutanol from cellulosic, non-food biomass.
The project would integrate Beta’s PROESA technology and Gevo’s GIFT and ATJ technologies, with anticipated production plants to be located where cellulosic feedstocks such as switchgrass, miscanthus, agriculture residues and other biomass will be readily available. The agreement also anticipates commercialization of the technology upon project success, which could enable renewably sourced, competitively priced jet fuel as well as other chemicals and fuels made from isobutanol.
Bio-isobutanol patent struggle: US District Court denies Butamax’s motion for preliminary injunction against Gevo
June 20, 2012
The US District Court of Delaware has denied the Motion for Preliminary Injunction sought by Butamax Advanced Biofuels, LLC (Butamax)—the biobutanol joint venture between BP and DuPont—against biobutanol company Gevo. (Case 1:11-cv-00054-SLR) This decision replaces a previous order enjoining Gevo from selling to new customers.
Gevo for now is clear to to sell in any market, to any customer, in any region, it said. The company yesterday signed a collaborative agreement with representatives from the Malaysian government’s East Coast Economic Region Development Council (ECERDC), Malaysian Biotechnology Corp (BiotechCorp) and the State Government of Terengganu with the intent to site a cellulosic biomass isobutanol facility in Southeast Asia. (Earlier post.)
Obama Administration releases National Bioeconomy Blueprint; health, food, energy and environment
April 26, 2012
The White House today released a national Bioeconomy Blueprint, a comprehensive approach to harnessing innovations in biological research to address national challenges in health, food, energy, and the environment. In coordination with the Blueprint’s release, Federal officials also announced a number of new commitments to help achieve the Blueprint’s goals.
The National Bioeconomy Blueprint describes five strategic objectives for a bioeconomy with the potential to generate economic growth and address societal needs. Although progress is being made in all of these areas, according to the Blueprint, much work remains if the United States is to remain competitive. The objectives are: