The production of biofuels and platform chemicals via gas fermentation is a rapidly commercializing technology for high volume, sustainable, production of fuels and chemicals. LanzaTech is commercializing a complete process platform to allow the continuous biological production of fuels and an array of chemicals intermediates from gases at scale. To date, this technology has been successfully demonstrated with such diverse gas streams as by-product gases from steel making, reformed natural gas, syngas produced from gasified biomass and municipal solid waste. Together with partners at PNNL the company has successfully piloted a catalytic process for the production of jet fuel from ethanol. This will allow hydrocarbon fuels to be produced form sustainable resources at scale in an integrated hybrid process.

Natural gas is currently one of the most economical sources of carbon and is second only to coal in terms of high carbon abundance and low carbon cost. Methanotroph bacteria use methane in natural gas as the sole carbon source to support cellular metabolism and growth. Natural gas is an attractive potential feedstock for microbial bioconversion efforts because, unlike sugar, it is a highly reduced form of carbon, allowing conversion of the methane substrate into reduced products with high stoichiometric yields. The objective of Intrexon’s natural gas upgrading program is to develop methanotroph biocatalysts for industrial-scale bioconversion of natural gas to chemicals, lubricants and fuels. Intrexon’s unique cellular engineering capabilities enable genetic manipulation of the methanotroph bacterium to convert natural gas to higher carbon content compounds at ambient temperatures and pressures, thereby reducing capex and opex requirements compared to standard gas to liquid (GTL) processes. Unlike other industrial hosts such as E. coli and S. cerevisiae, methanotrophs are challenging to genetically engineer as the requisite technologies are generally not available and detailed regulatory and physiological information is lacking. Intrexon has developed an advanced suite of technologies that enables rapid genetic engineering of methanotroph bacteria. Using these technologies, we have generated strains with increasing productivity for upgrading natural gas to higher value fuels and chemicals including isobutanol and farnesene. A pilot plant that incorporates downstream processing has been built and is currently operating at Intrexon’s facility in South San Francisco.

Mango Materials, based in the San Francisco Bay Area, uses a patented, low impact, and energy efficient biological process to produce materials from methane gas. This methane can be from “waste” sources such as water treatment plants, landfills, agricultural facilities, and even abandoned coal mines. To produce this polymer, non-genetically modified bacteria are cultivated and specific conditions are applied to stimulate production of the biopolymer polyhydroxyalkanoate (PHA). This talk will discuss the use of methane as a feedstock, scaling up bioprocesses, the end-of-life options for PHA, and the journey towards commercialization.

Novel microbial routes such as the isoprenoid pathway lead to multiphase fermentations where the product forms a volatile (e.g. isoprene, monoterpenes), an organic phase (e.g. sesquiterpenes) or solids (e.g. higher terpenes), with broad range of applications including fuels, (fine) chemicals and pharma. These phase-separating products offer great opportunities for cost reduction through integrated product recovery during fermentation. In this contribution we illustrate how we are approaching integration and scale-up at early stages of bioprocess development, focusing on our work on fermentation processes containing an organic phase.

In the extracellular production of long chain hydrocarbons and in extractive fermentations, the organic phase forms oil droplets dispersed in the fermentation broth. The turbulent conditions in the bioreactor and the presence of surface active components result in product stabilisation in the form of an emulsion. In a Dutch Public-Private partnership including Delft University of Technology (TU Delft) and the companies Delft Advanced Biorenewables (DAB) and the Bioprocess Pilot Facility (BPF), this issue is being addressed by: a) developing an oil recovery method for breaking up the emulsion, and b) designing and scaling up a bioreactor for in-situ oil recovery. The recovery method, based on gas injection, does not require additives, leads to more than 80% oil recovery, and is mild to the microbial cells. The integrated bioreactor, on the other hand, allows for fermentation, product recovery and cell recycle in one piece of equipment. A (non-hygienic) prototype has been tested up to 1 m3 scale, and a hygienic bioreactor is currently under construction.

Aqueous ethanol can be catalytically converted at high yield into jet, diesel, and gasoline blend stocks that are compatible with the current transportation fuel infrastructure. Vertimass LLC has the exclusive license to this novel catalyst technology developed by Oak Ridge National Laboratory This technology can also produce high value BTX (Benzene, Toluene, Xylene) coproducts that enhance revenues during low oil price environments. The Vertimass technology benefits from 1) single step ethanol conversion into hydrocarbon blend stocks with high yields, 2) no hydrogen addition, 3) high liquid blend stock yields, 4) operation at near ambient pressure and relatively low temperatures, 5) ability to process 5 to 100% ethanol concentrations, and 6) product flexibility to respond to changing markets. Although current production of ~15 billion gallons/year of ethanol by ~215 US corn ethanol plants saturates the market for 10% blends with gasoline, the fungible blend stocks derived from ethanol by application of Vertimass technology virtually eliminate this “blend wall” barrier and thereby expand the gasoline blending market for ethanol production from cellulosic biomass. In addition, the Vertimass process can be tailored to produce jet and diesel fuel blend stocks that can open up new markets for which ethanol is not well suited. Beyond providing ethanol producers flexibility to respond to changing fuel market demands with an add-on unit operation, the Vertimass approach can potentially lower their water demands, and conditions can be shifted to favor yields of valuable BTX co-products with higher carbon intensities than fuels that reduce overall GHG footprints.