Sep 20 2010
Researchers at Sharif University of Technology in Iran in association with their colleagues in Tohoku University in Japan invented a cost-effective method for the production of magnesium nanoparticles.
Researchers had to tackle many challenges in order to produce magnesium from magnesia due to its relatively high equilibrium temperature, reversibility of the reaction, and the production of micro-structured and flammable products. However, the reversion of the reaction in the products in gas phase can be prevented by creating a high rate cooling. Moreover, the nano-structured products can be synthesized in an appropriate protective atmosphere.
Dr Mohammad Nusheh, a PhD student in Materials Engineering, told the news service of Iran Nanotechnology Initiative Council that the objective of the research was to use the mechanical milling process in order to activate the reactants.
“The reaction temperature decreases noticeably by using this process and the kinetics of the reactions speed up in lower temperature ranges,” he said.
He studied the kinetics of carbothermic reduction reaction for magnesia through a mechanical activation process.
For this purpose, Nusheh chose a mixture of magnesia and graphite powders as the raw materials, and he applied high-energy mechanical milling process on them at different time intervals.
The results show that the mechanical activation has a significant effect on the progress of carbothermic reduction reaction of magnesia. In addition, milling reduces the initial temperature of the reduction reaction. This effect is caused by the reduction in the size of magnesia crystallites down to nanometric scale, the formation of amorphous graphite phase, and the intense increase in the interface of the powder particles.