85-2 Magnetic Stirrer

Hot Plate with Digital Temperature Display

by Duda Energy

Magnetic stirrers employ magnetic fields to cause a stir bar immersed in a liquid to spin very quickly, thus stirring it. These magnetic stirrers are often used in laboratories for mixing of liquids at an even speed.

This model is widely used in universities, environmental protection, scientific researching, chemical industry, hygiene and disease controlling, medical treatment etc.

This model has a digital temperature display and thermostatic control, thus making it more convenient to use in heat sensitive applications.

Method of Application:

Plug in the power supply. Pour the liquid to be tested into a beaker and then place the beaker on the heating plate. Put the stir bar and temperature sensor into the middle of the beaker. Turn on the power switch and the heating switch. Set the temperature according to the specific application and adjust the motor rotating speed.

Use in Biodiesel
Magnetic stirrers are great for stirring during a titration. While the stirrer does the mixing, a user can determine a more accurate titration by mixing the chemicals in a more even and controlled manner. The consistent rate of stirring can easily be achieved with the stirrer for concentration on the titration process itself and addition of catalyst solutions.
Magnetic stirrers may also be used for biodiesel test batches. The larger stir bars can easily create a good amount of agitation for the biodiesel process.

Stir Bar Sizing

The size of the stir bar to be used depends on the individual application. Keep in mind that a larger stir bar is not necessarily better. Larger stir bars have lower maximum spinning speeds. When the speed of a stir bar is too much for its size, it will jump around and skip inside of the beaker. Slippery and viscous liquids such as oils will also cause this to happen faster than non-slippery fluids like water.

If the container which holds the working fluid is rounded, it is recommended to use a stir bar with a pivot ring to help aid the spinning. Pivot rings also eliminate friction loss in flat bottom containers but they may also be a little noisy from rattling. If the container is very round, it is best to use an oval stir bar.