The use of argon as carrier gas in the microdetermination of oxygen in organic compounds

Argon is recommended as carrier gas in order to improve the efficiency of the method for the microdetermination of oxygen in organic compounds. To demonstrate that the use of argon is advantageous, parallel determinations were performed on a series of organic and inorganic compounds to establish the maximum amounts of substance quantitatively pyrolysable under normal analytical conditions. With argon, the maximum amount of the organic compound giving correct results was usually remarkably increased at all stages of the working life of the tube. This greater efficiency of the system in the conversion to carbon monoxide leads to higher reliability, allows a substantial decrease in the analysis time, and prolongs the life of the filling. The inconvenience of positive blank values with argon can be avoided if reaction tubes of very pure quartz are used.