A typical microwave acid digestion can be completed in a matter of minutes, whereas the same conventional hot plate digestion can take hours.
Microwave digestion usually involves placing a sample in an acid solution and heating to high temperature and pressure.
However, these extreme conditions will dissolve most materials, but is potentially quite dangerous.
Both HDPE and soil can be digested in concentrated HNO.
According to Howard M. Kingston of the National Bureau of Standards (NBS), Microwave digestion "is a new, more rapid tool for the analytical chemist involved in sample preparation, and it is capable of doing some preparations more reliably and accurately than can be done by conventional methods
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