Hydrogen Production from Waste Vegetable Oil

Scientists at the University of Leeds have found a new way to produce hydrogen fuel from waste vegetable oil that promises to be cleaner and require less energy input than conventional forms of hydrogen production.

According to the team behind the research, not only does the new process generate some of the energy needed to make the hydrogen gas itself, it is also essentially carbon-neutral.

The traditional and most common way to produce hydrogen gas, is to steam-reform it from fossil fuels, like natural gas. This process requires high temperatures of around 800 degrees, making it inefficient, expensive and still means reliance on a fossil fuel source. Producing hydrogen from waste vegetable oil using these techniques requires even higher temperatures making it an expensive and environmentally unfriendly process.

However, the new two-stage process is self-heating. To begin, a nickel catalyst is blasted with air to form nickel oxide – an ‘exothermic’ process that raises the starting temperature of 650 degrees by another 200 degrees, reducing the energy needs to reach the correct temperature. The waste vegetable oil and steam mixture then react with the hot nickel oxide to make hydrogen and carbon dioxide.

The researchers also added a special ‘sorbent’ material to trap all the carbon dioxide produced, leaving them with pure hydrogen gas. This trick eliminated the greenhouse gas emissions and also forced the reaction to keep running, increasing the amount of hydrogen gas produced.

The technology can be operated at any scale. It is just as suitable for use at a filling station as at a small power plant. The aim is to produce electricity locally using hydrogen-powered fuel cells, cutting the amount of energy lost during transmission down power lines.