Displacement inserts are often recommended for use with open bath Huber models (e.g. Ministats), when they are connected to a jacketed lab reactor (such as Reactor-Ready) as opposed to when placing items in the bath.
The purpose of the displacement insert is to take up some of the volume of the bath (in place of oil), reducing three potential issues to improve performance:
- To change the vessel jacket temperature, the Huber needs to change the temperature of all the oil in the bath too, which takes time. Reducing the amount of oil by using the displacement insert can enable faster temperature change.
- Because the baths are open to atmosphere (exposed to oxygen and water vapour), rather than being a sealed system like Unistats, the oil is likely to degrade more quickly. The displacement insert reduces exposure, so the oil can last longer.
- Oil may overflow if it expands significantly. Also, the larger the volume, the greater the oil will expand by when it is heated. The displacement insert reduces the oil volume and hence amount of expansion, and also acts as a safe location for oil to expand into rather than overflowing from the bath.
NB. Huber Unistats have a different, more advanced design than bath units. Unistats are hydraulically sealed, with a smaller internal volume. Displacement inserts are not applicable.