Jump to main content.

EPA Patents

A patent is an exclusive grant or property right given by the government to the inventor. A patent prevents others from making, using, or selling the invention for a period of 20 years without a license to do so. The inventor or owner of the patent can grant rights of the invention to others.

In general, government-funded technology patent rights are assigned to the government. Under the Federal Technology Transfer Act (FTTA), the government provides a portion of the royalties of a licensed patent to the EPA inventor. Practically anything human-made, as well as the process for making it, can be patented, provided it is new, useful, and unobvious. Improvements to an existing patent may also be patented. If patents are licensed, both the inventors and the sponsoring laboratory are entitled to a percentage of any royalties.

The FTTA, enacted by Congress in 1986, builds upon previous legislation and improves access to federal laboratories by private industry, consortia, academia, trade associations, and state and local governments. It also specifically requires that government-employed inventors share in the royalties received from their inventions. The goal of this legislation is to more efficiently and effectively put federally funded technology to use in real-world applications. This can be realized through the cooperation of non-federal parties and federal laboratories on specific research and development projects, as well as by licensing out federally-developed and patented inventions.

The benefits of moving federally-developed technologies into the marketplace are numerous. The public benefits by receiving improved products and obtaining a better return on their investment to government research programs. External parties benefit through the ability to leverage their research dollars and license new technologies for commercialization. The EPA benefits for many of the same reasons. EPA is able to better advance environmental efforts by getting new technologies into the marketplace quickly, can better leverage research and development dollars, and has the opportunity to collaborate with peers outside the Agency.

For more information about patents and licensing of inventions, please visit the EPA technology transfer web site. The EPA FTTA program is managed by the Office of Science Policy, within EPA's Office of Research and Development (ORD).

Following are a list of all EPA patents, a list of new EPA patents, and summaries of EPA patents by general topic area.


In-Situ Hybridization Probes for the Detection of Microsporidial Species (6,855,498)

Inventors: Jeffrey Hester, Alan Lindquist, Frank Schaefer
Issued February 18, 2005

Low Emission Diesel Combustion System with Low Charge-air Oxygen Concentration Levels and High Fuel Injection Pressures (6,857,263)

Inventors: Charles Gray, David Haugen
Issued February 22, 2005

Methods of Operating a Series Hybrid Vehicle (6,876,098)

Inventor: Charles Gray
Issued April 5, 2005

Hydrophilic Mixed Matrix Materials Having Reversible Water Absorbing Properties (6,881,364)

Inventors: Leland Vane, Ravi Ponangi
Issued April 19, 2005

HCCI Engine with Combustion-Tailoring Chamber (6,910,459)

Inventors: Ruonan Sun, Karl Hellman, Charles Gray
Issued June 28, 2005

Method for Evaluating and Affecting Male Fertility (6,965,016)

Inventor: Gary Klinefelter
Issued November 15, 2005


Fuel Tank Ventilation System (6,681,789)

One source of air pollution is "evaporative emissions" from vehicle fuel tanks. These emissions occur each day for all vehicles with fuel in the tank, even when stationary. Charles Moulis and Leon Jones of EPA's National Vehicle and Fuel Emissions Laboratory (NVFEL) in Ann Arbor developed a fuel tank ventilation system that comprises a fuel tank and a bladder within the fuel tank that vents to the atmosphere and inflates and deflates with a variable volume of air. The exchange of air between the atmosphere and the bladder substantially maintains the vapor space within the fuel tank at atmospheric pressure and only air from the bladder is vented from the fuel tank because the air within the bladder is isolated from the fuel vapor. The system substantially prevents evaporative emissions from vehicle fuel tanks.

Variable Compression Ratio Engine (6,752,105)

Current automotive powertrain designs employ an internal combustion engine (ICE). Although the demands of normal driving call for a wide range of power demands and speeds, the best energy conversion efficiency of an ICE is experienced over only a relatively narrow range of loads and speeds. Charles Gray of NVFEL developed an improved system for generating a variable compression ratio within an ICE. The engine may operate at more than one distinct compression ratio, selectable during engine operation. As a result, an engine using this technology operates near its most efficient operating range during the majority of driving, while providing intermittent high power capability in a way that does not lead to undesirable side effects.

Treating Liquids Containing Organic Compounds (6,755,975)

Liquids containing organic compounds and water occur throughout industry, making the water unfit for reuse or discharge. Leland Vane and Frank Alvarez of EPA's National Risk Management Research Laboratory (NRMRL) in Cincinnati, along with several scientists from Membrane Technology and Research, Inc., developed a process for separating a liquid containing an organic compound and water, using a combination of pervaporation and reflux condensation that can treat streams containing one or more dissolved organic compounds to produce a product stream containing as much as 90 wt % or more organic compound. This can be achieved even when the organic compound is present at relatively low concentrations in the feed. The process can also be used to dehydrate organic liquids in which water is dissolved, to yield an organic product containing as little as 1 wt % water or less, and a relatively clean water stream.

Selective Oxidation of Organic Chemicals (6,777,374)

The chemical manufacturing industry generates more than 1.5 billion tons of hazardous waste and 9 billion tons of non-hazardous waste annually. Cleaner products methods can be achieved by adopting "green synthetic" methods. Endalkachew Sahle-Demessie, Michael Gonzalez and Subhas Sikdar of NRMRL, along with scientists from the University of Cincinnati, developed a process for partial oxidation of organic compounds in the gas phase to produce valuable compounds. This results in a clean production technology that minimizes waste by selectively producing partial oxygenates and producing less by-products and pollutants than conventional oxidation reactions.

Method of Treating Fuel Exhaust (6,779,339)

New emission reduction standards for lean burn heavy-duty diesel engines are to be implemented starting in model year 2007. The new standards will require catalysts and systems that can suppress the emission of oxides of nitrogen (NOx) from these engines into the atmosphere. Christopher Laroo, Charles Schenk, Joseph McDonald, Byron Bunker, Brian Olson, Robert Moss, Daniel Stokes, and Paul Way of NVFEL developed a method and apparatus for desulfating NOx adsorber catalysts in a multi exhaust path flow system utilizing in-exhaust fuel injection and exhaust flow bypass. This method minimizes temperature extremes on the surface of the NOx adsorber, while achieving the precise temperatures required for desulfation. Thus, overall thermal degradation of the adsorber catalyst due to high temperatures is kept to a minimum or ultimately eliminated.

High Pressure Fuel System for Common Rail Application (6,786,205)

Currently, the automotive industry does not have a reliable high pressure fuel system which is compatible with alcohol fuels. In conventional hydraulically intensified fuel injectors, low pressure fuel enters the injector and is intensified in pressure by a hydraulic piston. The injector and intensifier are contained in a single unit, which requires separate hydraulic and fuel supplies. Mark Stuhldreher and Andrew Moskalik of NVFEL developed a system that separates the intensifier from the injector and provides a structure having fewer parts to wear and fewer hydraulic lines to potentially leak. The system has at least two intensifier units which use hydraulic fluid to pressurize fuel supplied to a common rail. These intensifiers alternately supply high pressure fuel to the common rail and refill with low pressure fuel.

Cylinder Coolant Control System (6,810,838)

Conventional systems for cooling engine cylinder heads provide coolant patterns which go from one end of the cylinder head and block to the other. This approach is successful in that engines generally do not overheat, but temperatures may vary between cylinders in a way that some cylinders are cooled just barely enough, while other cylinders are overcooled. This can affect the distribution of fuel and air into the cylinders and the initiation of combustion, such that not all of the cylinders attain optimum performance due to cylinder-to-cylinder cooling differences. Karl Hellman of NVFEL developed a cooling system for an engine including a cylinder block having multiple cylinders covered and closed by a cylinder head. The coolant system includes an inlet rail and an outlet rail located on opposing sides of the cylinder head and a pump for feeding coolant flow through a discharge line into the inlet rail. A control valve and an associated temperature sensor are provided within each of the coolant flow passages and a controller individually controls each of the control valves in accordance with the signal received from its associated temperature sensor.

Exhaust Aftertreatment System (6,820,417)

The control of nitrogen oxide (NOx) emissions from internal combustion engines and particulate matter (PM) emissions from compression (diesel) combustion engines is an environmental problem. Gasoline engine vehicles use three-way catalysts to control such emissions, because their exhaust gases lack oxygen. But so-called "lean-burn" gas engines and diesel engines have enough oxygen in their exhausts that conventional catalytic systems are not effective. Charles Schenk of NVFEL, along with co-inventors from Analytical Engineering Inc., developed a diesel engine exhaust aftertreatment system that reduces NOx and PM. The aftertreatment system may include one or more exhaust flow paths, or "legs", and each leg of the exhaust system may contain any combination of an injector, NOx adsorber element(s), with an upstream or downstream diesel oxidation catalyst, and optional upstream or downstream particulate trap or other substrate.

Biomass Concentrator Reactor (6,821,425)

Water quality is of increasing importance, as many of the impurities in water have been identified to have deleterious effect in the environment or for plant or animal life. Both water from streams, rivers, etc. and wastewater require treatment to reduce the pollutants in the water to acceptable levels. Wastewater can be purified by a variety of methods, including mechanical purification by sedimentation or filtration (usually surface waters for drinking water treatment), and chemical purification by, for example, the addition of ozone or chlorine (not practical as stand-alone for wastewater treatment). Biological wastewater treatment is by far the most widely used technology for treating municipal and industrial wastewater in the U.S., and it is gaining popularity for the treatment of drinking water. Albert Venosa of NRMRL and Makram Suidan of the University of Cincinnati, developed a gravity-flow biomass concentrator reactor which effectively retains and concentrates suspended solids from the water treated. The reactor can be used under either aerobic or anaerobic conditions.

Electronic Caliper (6,829,839)

A standard test for immune sensitivity is to inject a tiny amount of test material into the ear of a mouse. If, after a time, the ear becomes edematous, the test is considered positive. A similar test is done on rat foot-pads. The normal way to measure this edema has been to use a precision caliper with a dial face graduated in 100ths of a millimeter. This device was made for measuring hard materials such as metal, plastic, paper, etc., and works very well for such purposes. However, it applies a significant force, squeezing whatever it measures, which is not ideal for soft biological tissues because the squeezing action reduces the thickness and diminishes the resulting measurement. Paul Killough of EPA National Health and Environmental Effects Laboratory (NHEERL) in Research Triangle Park, NC invented a device that eliminates most of the internal mechanical parts of the commonly used gauge and substitutes an electronic distance measuring device, thereby avoiding most of the friction believed to cause the problems seen in that gauge.

Local Navigation

Jump to main content.