In a pioneering research, scientists claim to have produced the world’s first magnetic soap that is composed of iron-rich salts dissolved in water.
A team at Bristol University says that its soap, which responds to a magnetic field when placed in solution, would calm all concerns over the use of surfactants in oil-spill clean-ups and revolutionise industrial cleaning products.
For long, researchers have been searching for a way to control soaps (or surfactants as they are known in industry) once they are in solution to increase the ability to dissolve oils in water and then remove them from a system.
The Bristol University team produced the magnetic soap by dissolving iron in a range of inert surfactant materials composed of chloride and bromide ions, very similar to those found in everyday mouthwash or fabric conditioner.
The addition of the iron creates metallic centres within the soap particles, say the scientists led by Julian Eastoe.
To test its properties, the team introduced a magnet to a test tube containing their new soap lying beneath a less dense organic solution, the ‘Angewandte Chemie’ journal reported.
When the magnet was introduced the iron-rich soap overcame both gravity and surface tension between the water and oil, to levitate through the organic solvent and reach the source of magnetic energy, proving its magnetic properties.
Once the surfactant was developed and shown to be magnetic, the scientists took it to Institut Laue-Langevin (ILL), the world’s flagship centre for neutron science, to investigate the science behind its remarkable property.
When surfactants are added to water they are known to form tiny clumps (particles called micelles).
At ILL, the scientists used a technique called “small angle neutron scattering (SANS)” to confirm that it was this clumping of the iron-rich surfactant that brought about its magnetic properties.
The potential applications of magnetic surfactants are huge, say the scientists.
Prof. Eastoe said, “As most magnets are metals, from a purely scientific point of view these ionic liquid surfactants are highly unusual, making them a particularly interesting discovery.
“From a commercial point of view, though these exact liquids aren’t yet ready to appear in any household product, by proving that magnetic soaps can be developed, future work can reproduce the same phenomenon in more commercially viable liquids for a range of applications from water treatment to industrial cleaning products.”
