The tank technology for low-pressure storage of natural gas on vehicles, developed in Peter Pfeifer’s lab, will be showcased at the 6th annual Missouri Tech Expo, Oct. 15, 2015, http://motechexpo.missouri.edu/. Adsorbed Natural Gas Products, Inc., http://www.angpinc.com/about-angp/, holds a license for commercialization of the technology for light-duty and heavy-duty vehicles. Bob Bonelli, Founder and CEO of ANGP, will give a keynote presentation, “The Next Big Thing,” about the roadmap for the first commercial fuel tanks to reach the market in 2016. The presentation will include a vehicle demonstration.
Prof. Peter Pfeifer received a 2015 FastTrack award, under which the UM Office of Research and Economic Development funds “development, testing, prototype construction, or specific market research” to move university inventions further down the commercial pipeline, http://www.umsystem.edu/ums/aa/fundingopps/fasttrack. The $50,000 award is for an upgrade of the adsorbed natural gas tank for low-pressure storage on next-generation clean vehicles, which Peter’s team built and put into service in 2014 under a $1.3M California Energy Commission contract. The core of the tank is monolithic carbon, originally made from corncob, with world-record storage capacity. Two patents have been issued for the production of such carbon, “High surface area carbon and process for its production” (#8,691,177 (2014); #8,926,932 (2015)), and have generated two licenses. The licenses are for on-board, low-pressure storage of natural gas as engine fuel on vehicles (Adsorbed Natural Gas Products, Inc., http://www.angpinc.com/about-angp/) and for large-scale transport of natural gas in virtual pipelines, respectively. The FastTrack award funds an upgrade of the 2014 tank to a test rig for measurements of heat transfer, adsorbent durability, fueling rates, etc. It will support current and future licensees (aerospace, maritime shipping of natural gas, portable power sources) in 1st-to-market commercial products.
Our research was recently spotlighted in the Columbia Daily Tribune. Here is an excerpt:
“The city of Columbia might be a test case for cutting-edge improvements to natural gas-powered vehicles as it prepares to bring in a compressed natural gas station and experiment with other advanced natural gas technologies… …A group of University of Missouri researchers hopes to make natural gas available to a wider array of vehicle models through the development of absorbed natural gas, or ANG, technology, which can provide the same amount of energy as compressed natural gas tanks while taking up less space and requiring less pressure — about 500 psi — thus making the tanks more suitable for lighter vehicles such as passenger cars…”
Click Here to Read the Full Article in the Columbia Daily Tribune
We report Fourier transform infrared spectroscopy (FTIR) studies of boron-doped activated carbons. The functional groups for hydrogen adsorption in these materials, the boron-related chemical bonds, are studied by comparing the activated carbon materials with and without boron doping. The activated carbon materials are prepared from corncob biomass waste feedstock through KOH activation, yielding adsorbents with a high surface area. Boron atoms are doped into the activated carbon by vapor deposition of decaborane up to a solubility of 6.8 weight percent.
Extra boron atoms (2-3 weight percent) are located on the surface of the carbon matrix. Results from conventional FTIR show serious spectral broadenings and band overlaps. To overcome the spectral broadenings and band overlaps, the sample concentration is reduced to a very low weight percent (0.03%) of activated carbon in KBr, and spectra are acquired by using microscopic FTIR. Activated boron carbide is used as a reference material to validate the boron-carbon bond in the nanoporous materials. For activated carbon doped via vapor deposition of decaborane, the substitutions of carbon atoms with boron atoms is confirmed using microscopic FTIR through the appearance of boron-carbon bonds, although it cannot be observed with conventional FTIR.
Romanos, J.; Beckner, M.; Stalla, D.; Tekeei, A.; Suppes, G.; Jalisatgi, S.; Lee, M.; Hawthorne, F.; Robertson, J. D.; Firlej, L.; Kuchta, B.; Wexler, C.; Yu, P.; Pfeifer, P., Infrared study of boron-carbon chemical bonds in boron-doped activated carbon. Carbon.
Hydrogen adsorption in slit shaped pores built up from truncated graphene fragments has been simulated using Grand Canonical Monte Carlo technique and the influence of pore wall edges on hydrogen storage by physisorption has been analyzed. We show that due to the additional gas adsorption at the pore edges the adsorbed gravimetric amount significantly increases (by a factor of two) with respect to models of pores with infinite graphene walls. The contribution of the edges’ adsorption to the total hydrogen uptake is independent of the pore wall shape but it depends on its surface. We also show that the maximum of the excess adsorption shifts towards higher pressures when the edge contribution increases.
This information can be used to characterize experimentally structures of porous adsorbents and complement pore size distribution analysis usually performed with gases others than hydrogen. We suggest that porous carbons built from polycyclic hydrocarbons can achieve storage performances required for practical applications.
Firlej, L.; Kuchta, B.; Lazarewicz, A.; Pfeifer, P., Increased H2 gravimetric storage capacity in truncated carbon slit pores modeled by Grand Canonical Monte Carlo. Carbon.
Goal of ARPA-E project to achieve 10X reduction in station costs and cut re-fueling time for Natural Gas (NG) vehicles from a whole work day to under one hour.
Developing unique approach to re-fueling that would replace more expensive and complex compressor technologies used today
Initial focus will be on re-fueling stations for fleet vehicles, with an eye to passenger vehicles in the future
In what could help fuel widespread adoption of NG vehicles in the US and globally, GE researchers, in partnership with Chart Industries and scientists at the University of Missouri, have been awarded a program through Advanced Research Projects Agency for Energy (ARPA-E) to develop an affordable at-home refueling station that would meet ARPA-E’s target of $500 per station and reduce re-fueling times from 5-8 hours to less than 1 hour. Continue reading GE and MU Researchers Developing At-Home Refueling Station for NG Vehicles
Credit: Douglas Fraser
Our research has been just featured in an article in the Wall Street Journal
“Meanwhile, researchers at the University of Missouri have developed a smaller tank that allows natural gas to be stored at a much lower pressure by keeping it in a material essentially made out of corncobs turned into charcoal briquettes. Early tests of the tank on a natural-gas pickup truck have worked well, according to researchers.”
Romanos, J. et al. Nanospace engineering of KOH activated carbon. Nanotechnology 23, 015401 (2012).
This paper demonstrates that nanospace engineering of KOH activated carbon is possible by controlling the degree of carbon consumption and metallic potassium intercalation into the carbon lattice during the activation process. High specific surface areas, porosities, sub-nanometer (<1 nm) and supra-nanometer (1–5 nm) pore volumes are quantitatively controlled by a combination of KOH concentration and activation temperature. The process typically leads to a bimodal pore size distribution, with a large, approximately constant number of sub-nanometer pores and a variable number of supra-nanometer pores. We show how to control the number of supra-nanometer pores in a manner not achieved previously by chemical activation. Continue reading Nanospace engineering of KOH activated carbon
Burress, J. et al. Hydrogen storage in engineered carbon nanospaces. Nanotechnology 20, 204026 (2009).
It is shown how appropriately engineered nanoporous carbons provide materials for reversible hydrogen storage, based on physisorption, with exceptional storage capacities (~80 g H2/kg carbon, ~50 g H2/liter carbon, at 50 bar and 77 K). Nanopores generate high storage capacities (a) by having high surface area to volume ratios, and (b) by hosting deep potential wells through overlapping substrate potentials from opposite pore walls, giving rise to a binding energy nearly twice the binding energy in wide pores. Experimental case studies are presented with surface areas as high as 3100 m2 g−1, in which 40% of all surface sites reside in pores of width ~0.7 nm and binding energy ~9 kJ mol−1, and 60% of sites in pores of width>1.0 nm and binding energy ~5 kJ mol−1. Continue reading Hydrogen storage in engineered carbon nanospaces
Firlej, L., Roszak, S., Kuchta, B., Pfeifer, P. & Wexler, C. Enhanced hydrogen adsorption in boron substituted carbon nanospaces. The Journal of chemical physics 131, 164702 (2009).
Activated carbons are one of promising groups of materials for reversible storage of hydrogen by physisorption. However, the heat of hydrogen adsorption in such materials is relatively low, in the range of about 4–8 kJ/mol, which limits the total amount of hydrogen adsorbed at P = 100 bar to ∼ 2 wt % at room temperature and ∼ 8 wt % at 77 K. To improve the sorption characteristics the adsorbing surfaces must be modified either by substitution of some atoms in the all-carbon skeleton by other elements, or by doping/intercalation with other species. In this letter we present ab initio calculations and Monte Carlo simulations showing that substitution of 5%–10% of atoms in a nanoporous carbon by boron atoms results in significant increases in the adsorption energy (up to 10–13.5 kJ/mol) and storage capacity ( ∼ 5 wt % at 298 K, 100 bar) with a 97% delivery rate.