NOVELTY - The process involves producing a gas stream containing hydrogen gas from water electrolysis. The gas stream is passed through one or more polar liquid medium-containing chambers of a purification unit, such as scrubbing unit (3,10) and through the desiccation unit to remove substances other than hydrogen. The purified gas stream contacts hydrocarbon fuel such that hydrogen is introduced into the fuel to produce the enriched fuel. The enriched fuel is delivered to an engine (9). The liquid medium is a polar protic solvent or water. The desiccation unit is a molecular sieve trap (4) or zeolite.    USE - Process, particularly electrolytic process for enriching hydrocarbon fuel with hydrogen. Uses include but are not limited to petrol, diesel, liquefied petroleum gas, compressed natural gas, bio-diesel, and alcohols such as ethanol to be delivered to an internal combustion engine (claimed) such as petrol engine or diesel engine for vehicles, including marine and aviation vehicles.    ADVANTAGE - The engine is made to run on enriched hydrocarbon fuel, increasing fuel efficiency. Carbon footprint is reduced since fuel consumption is decreased. Nitrogen oxide production is reduced by displacement of nitrogen from the combustion engine and by more efficient combustion cycle in contained volume. Particulate production especially in diesel engines is reduced by increasing efficiency of combustion such that combustion products are almost exclusively gaseous. Engine wear is reduced by preventing carbon deposit build-up usually due to standard air-fuel mixtures. Existing engines can be cleaned of carbon deposits during the first 1000 to 2000 kilometers of operation after installation, optimizing engine conditions. Service interval for oil changes is increased since carbon contamination of oil does not occur while the system is run correctly. The system can be suited from one vehicle to another and optimized using programmable electronic fuel injection enhancer (EFIE) technology. Intrusion to other existing vehicle systems can be avoided, since the fuel enriching device is compact and requires minimal mechanical interfacing. Performance of poor grade hydrocarbon fuels can be increased by being enriched with hydrogen, allowing these fuels to still be used on vehicles. The system is versatile enough to adapt to wide range of engines and vehicles, including marine and aviation vehicles.    DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for the following:    (1) a device for enriching fuel; and    (2) an internal combustion engine.    DESCRIPTION OF DRAWING(S) - The drawing shows the block diagram of a system for enriching hydrocarbon fuels.    Scrubbing unit (3,10)    Molecular sieve trap (4)    Engine (9)    Relay (18)    Timer (19)