Cap for closing a sample container for microwave treatment and a method and sample assembly for performing microwave treatment

A sample assembly, comprising:

• a sample vessel;
• a cap closing said sample vessel, said cap containing:
• a closure body for closing said sample vessel and having a sealing surface, said closure body being fitted to said sample vessel and closes said sample vessel by said sealing surface when said cap is in a state fitted to said sample vessel;
• a spring-loaded pressure relief valve;
• at least one vent duct, said vent duct, said spring-loaded pressure relief valve and said closure body are configured in such a manner that said vent duct connects said closure body via said spring-loaded pressure relief valve to a surrounding area in such a manner that when a defined first pressure level is exceeded at said closure body excess pressure can escape through said vent duct into the area surrounding said cap;
• and
• a reservoir, wherein said reservoir and said vent duct are configured in such a manner that condensate precipitating in said vent duct accumulates in said reservoir when said cap is in the state fitted to said sample vessel.

A method for microwave treatment of samples, which comprises the steps of:

• sealing a sample in a sample vessel using a cap, wherein the cap containing:
• a closure body for closing the sample vessel and having a sealing surface, the closure body being fitted to the sample vessel and closes the sample vessel by the sealing surface when the cap is in a state fitted to the sample vessel;
• a spring-loaded pressure relief valve;
• at least one vent duct, the vent duct, the spring-loaded pressure relief valve and the closure body are configured in such a manner that the vent duct connects the closure body via the spring-loaded pressure relief valve to a surrounding area in such a manner that when a defined first pressure level is exceeded at the closure body excess pressure can escape through the vent duct into the area surrounding the cap;
• and
• a reservoir, wherein the reservoir and the vent duct are configured in such a manner that condensate precipitating in the vent duct accumulates in the reservoir when the cap is in the state fitted to the sample vessel;
• heating the sample by microwave radiation and a first pressure level exists in an inside of the sample vessel;
• venting excess pressure and vapors disposed within the sample vessel via the pressure relief valve and the vent duct to the area surrounding the cap;
• condensing the vapors escaping from the inside of the sample vessel as condensate in the vent duct;
• collecting the condensate in a reservoir;
• and
• evaporating the condensate.