Researchers at the Fraunhofer Institute for Chemical Technology ICT in Pfinztal have developed a method for safer production of nitroglycerine.
According to the scientists, the process is much safer due to the tiny quantities involved which means that less heat is generated.
Unlike a large agitating vessel that needs to be filled before the slow reaction proceeds, the microreactor works continuously.
The base materials flow through tiny channels into the reaction chamber in “assembly-line fashion“.
There, they react with one another for several seconds before flowing through other channels into a second microreactor for processing.
This is because the interim product still contains impurities that need to be removed for safety reasons.
“This marks the first use of microreactors in a process not only for synthesis of a material but also for its subsequent processing,“ observes Dr. Stefan Löbbecke, deputy division director at ICT.
While microreactors suggest themselves for explosive materials, this is not the only possible application.
Researchers at ICT build reactors for every chemical reaction conceivable – and each is tailored to the particular reaction involved.
An example is a microreactor that produces polymers for OLEDs. OLEDs are organic light-emitting diodes that are particularly common in displays and monitors.
The polymers of which the OLEDs are made light up in colours. Still, when they are produced – synthesised – imperfections easily arise that rob the polymers of some of their luminosity.
“Through precise process management, we are able to minimise the number of these imperfections,“ Löbbecke points out.
To accomplish this, researchers first analysed the reaction in minute detail: When do the polymers form? When do the imperfections arise? How fast does the process need to be?
“As it turns out, many of the reaction protocol that people are familiar with from batch processes are unnecessary. Often, the base materials don‘t need to boil for hours at a time; in many cases all it takes is a few seconds,“ Löbbecke said.