James Wegrzyn

Regeneration of aluminium hydride using dimethylethylamine

Aluminium hydride is a compound that is well known for its high gravimetric and volumetric hydrogen densities and favorable hydrogen storage properties. Tertiary amine–aluminium hydride complexes have gained interest due to their application as chemical reducing agents and in aluminium thin-film deposition. Various complexes of these amine alane compounds have been created and studied previously, but these compounds were not formed directly using pressurized hydrogen. Here, we demonstrate the direct reaction of catalyzed aluminium, a tertiary amine, and hydrogen in a common solvent proceeds to form an amine alane adduct at moderate pressures and temperatures. A complex of aluminium hydride has been formed with dimethylethylamine by this technique. A vibrational analysis of the product of these reactions by Raman and infrared spectroscopy is presented, including experimental and theoretical data. The results clarify the molecular and vibrational structure of amine alane complexes formed by direct hydrogenation and are compared with previously determined experimental information. In addition, we demonstrate a new method for the formation of triethylamine alane using the direct hydrogenation of dimethylethylamine and catalyzed aluminium followed by transamination with triethylamine. Finally, we propose a new low energy method to regenerate AlH3 from catalyzed aluminium and hydrogen gas.

Liquefied Natural Gas for Trucks and Buses

Liquefied natural gas (LNG) is being developed as a heavy vehicle fuel. The reason for developing LNG is to reduce our dependency on imported oil by eliminating technical and costs barriers associated with its usage. The U.S. Department of Energy (DOE) has a program, currently in its third year, to develop and advance cost-effective technologies for operating and refueling natural gas-fueled heavy vehicles (Class 7-8 trucks). The objectives of the DOE Natural Gas Vehicle Systems Program are to achieve market penetration by reducing vehicle conversion and fuel costs, to increase consumer acceptance by improving the reliability and efficiency, and to improve air quality by reducing tailpipe emissions. One way to reduce fuel costs is to develop new supplies of cheap natural gas. Significant progress is being made towards developing more energy-efficient, low-cost, small-scale natural gas liquefiers for exploiting alternative sources of natural gas such as from landfill and remote gas sites. In particular, the DOE program provides funds for research and development in the areas of; natural gas clean up, LNG production, advanced vehicle onboard storage tanks, improved fuel delivery systems and LNG market strategies. In general, the program seeks to integrate the individual components being developed into complete systems, and then demonstrate the technology to establish technical and economic feasibility. The paper also reviews the importance of cryogenics in designing LNG fuel delivery systems.

Natural Gas as a Future Fuel for Heavy-Duty Vehicles

In addition to their significant environmental impacts, medium-duty and heavy-duty (HD) vehicles are high volume fuel users. Development of such vehicles, which include transit buses, refuse trucks, and HD Class 6-8 trucks, that are fueled with natural gas is strategic to market introduction of natural gas vehicles (NGV). Over the past five years the Department of Energys (DOE) Office of Heavy Vehicle Technologies (OHVT) has funded technological developments in NGV systems to support the growth of this sector in the highly competitive transportation market. The goals are to minimize emissions associated with NGV use, to improve on the economies of scale, and to continue supporting the testing and safety assessments of all new systems. This paper provides an overview of the status of major projects under a program supported by DOE/OHVT and managed by Brookhaven National Laboratory. The discussion focuses on the programs technical strategy in meeting specific goals proposed by the N GV industry and the government. Relevant projects include the development of low-cost fuel storage, fueling infrastructure, and HD vehicle applications.

Low emissions class 8 heavy-duty on-highway natural gas and gasoline engine

The goal of this project was to demonstrate that a Mack E7G engine operating stoichiometric with Exhaust Gas Recirculation (EGR) and a three-way catalyst can meet the 2010 emission standards for heavy-duty on-highway engines. Results using natural gas and gasoline as the fuel are presented. The Mack E7G is currently a lean burn natural gas fueled engine, which was originally derived from the diesel engine. The calibration of the lean burn engine was modified to operate as a stoichiometric engine. An EGR system and a three-way catalyst were added to the engine. One of the lean burn natural gas ratings for this engine is 242 kW at 1950 rpm and 1424 N-m, at 1250 rpm. This rating was also used for the stoichiometric natural gas engine. Transient emissions and 13-mode steady-state emissions tests were conducted on the engine on natural gas. The engine meets the transient emission standards for 2010 for NO x , NMHC, and CO on natural gas. Steady-state results on the 13-mode test show this engine meets NO x , NMHC, CO and particulate matter emissions standards for 2010 on natural gas. Formaldehyde emissions are well below the ULEV and transient bus standards for heavy-duty vehicles on both the transient and steady state tests. Efficiency of the natural gas stoichiometric engine was comparable to a typical low emissions lean burn natural gas engine. Results with gasoline were conducted on the first seven modes of the 13-mode steady state test. The engine did not meet the emissions standards for 2010 on gasoline for this testing. Catalyst degradation from misfires while setting up the engine to operate on gasoline contributed to the higher than expected emissions.

Natural Gas as a Fuel Option for Heavy Vehicles

The U.S. Department of Energy (DOE), Office of Heavy Vehicle Technologies (OHVT) is promoting the use of natural gas as a fuel option in the transportation energy sector through its natural gas vehicle program [1]. The goal of this program is to eliminate the technical and cost barriers associated with displacing imported petroleum. This is achieved by supporting research and development in technologies that reduce manufacturing costs, reduce emissions, and improve vehicle performance and consumer acceptance for natural gas fueled vehicles. In collaboration with Brookhaven National Laboratory, projects are currently being pursued in (1) liquefied natural gas production from unconventional sources, (2) onboard natural gas storage (adsorbent, compressed, and liquefied), (3) natural gas delivery systems for both onboard the vehicle and the refueling station, and (4) regional and enduse strategies. This paper will provide an overview of these projects highlighting their achievements and current status. In addition, it will discuss how the individual technologies developed are being integrated into an overall program strategic plan.

Metal Hydrides for Hydrogen Storage

The emergence of a Hydrogen Economy will require the development of new media capable of safely storing hydrogen with high gravimetric and volumetric densities. Metal hydrides and complex metal hydrides, where hydrogen is chemically bonded to the metal atoms in the bulk, offer some hope of overcoming the challenges associated with hydrogen storage. Many of the more promising hydrogen materials are tailored to meet the unique demands of a low temperature automotive fuel cell and are therefore either entirely new (e.g. in structural or chemical composition) or in some new form (e.g. morphology, crystallite size, catalysts). This proceeding presents an overview of some of the challenges associated with metal hydride hydrogen storage and a few new approaches being investigated to address these challenges.