A research team from the Federal University of Technology Owerri in Nigeria has reviewed studies from around the world and found that mixing small amounts of water into diesel fuel can dramatically cut harmful emissions, without redesigning the engine.
The approach, called Water-in-Diesel Emulsion, disperses tiny water droplets evenly through the fuel using surfactants. Compared with conventional diesel, the treated fuel reduced nitrogen oxide emissions by as much as 67 percent and particulate matter by up to 68 percent, according to lead author Dr. Chukwuemeka Fortunatus Nnadozie and co-author Professor Emeka Emmanuel Oguzie.
When the fuel is injected and ignited, the trapped water rapidly turns to vapor, creating a tiny burst that breaks the fuel into finer droplets and mixes it more completely with air. That more complete combustion, plus lower peak temperatures from the water, is what drives down soot and nitrogen oxide output. Properly formulated mixtures stayed stable for up to 60 days, and several experiments even found improvements in how efficiently the engines converted fuel into power.
Because it works in existing engines, the researchers say the technique could offer an immediate path toward lower emissions for diesel vehicles and industrial power systems in developing and developed countries alike.
