Sample injection system for chemical analyzer and method of sample analysis

A method for thermal analysis of a sample selected from a solid and a liquid wherein the sample is exposed to an elevated temperature effective for volatilizing at least a portion of the sample and the resulting products are passed in a carrier gas stream to at least one detecting means capable of producing a signal responsive to a change in the composition of the carrier gas stream, the method comprising:

• introducing a measured sample into a first chamber which is in carrier gas flow communication with said detecting means and which is maintained at a temperature lower than said elevated temperature;
• allowing the carrier gas to flow across the sample to the detecting means for a time effective for establishing a substantially stable response signal representative of the carrier gas;
• subsequently transferring the sample from the first chamber to a second adjoining chamber which has been preheated to said elevated temperature and heating the sample to said elevated temperature thereby producing a gaseous product;
• and
• passing said gaseous product in the carrier gas stream to the detecting means and producing a signal indicative of the presence of the gaseous product.

A method for the thermal analysis of a geological sample wherein the sample is exposed to an elevated temperature effective for volatilizing at least a portion of the sample, the method comprising:

• introducing a measured geological sample into a first chamber which is in carrier gas flow communication with a detecting means capable of producing a signal responsive to a change in the composition of the carrier gas stream, said first chamber being maintained at a temperature which is lower than said elevated temperature;
• allowing the carrier gas to flow in contact with the sample and thence to the detecting means for a time effective for establishing a substantially stable response signal respresentative of the carrier gas;
• subsequently transferring the sample from the first chamber to an adjoining second chamber which has been preheated to said elevated temperature and heating the sample to said elevated temperature thereby producing a thermal extraction product;
• and
• passing said thermal extraction product in the carrier gas stream to the detecting means and producing a signal indicative of the presence of the thermal extraction product.