Direct Determination of Total Oxygen in Oils

Determination of Oxygen in Organic Compounds.

“…In a significant study (44), Marks applied the method to the determination of oxygen in oxidized oils, obtaining a precision of ±0.1 per cent or better and an expected accuracy compared to calibration determinations of ±0.2 per cent or better. In general, aliphatic compounds are readily cracked to gaseous products between 600 and 800°C.…”

“…ter Meulen (55) advised the use of iron-free nickel oxide in preparing the catalyst, since iron slows up the rate of reduction. (c) Determination of water formed Various substances have been proposed and used as absorption agents for the water produced in the reaction, including calcium chloride (29, 48, 50, 73), calcium oxide (95), calcium sulfate (2,25,34,37,44), lithium hydroxide (95), magnesium perchlorate (37), and sodium hydroxide (29, 74). These, of course, involve the gravimetric determination of the water formed.…”

The teaching of microchemistry

“…A brief survey is given of the problems involved in the determination of oxygen in which the student is shown the relative advantages and drawbacks in the Ter Meulen hydrogenation and in the oxidation method, when each is used for the determination of the element oxygen in the presence of nitrogen and sulfur (8, 9). The future possibilities of cinnamoyl chloride and alpha naphthylchlorophosphine as reagents for water are discussed in this connection as well as the use of cracking and methanation catalysts (10,11,12).…”

Direct Determination of Oxygen in Organic Compounds by Hydrogenation

“…and Fulton (8) and Russell and Marks (9) reported an improved method for the direct determination of oxygen in organic compounds containing only carbon, hydrogen, and oxygen and in compounds also containing nitrogen. Later Marks (4) applied the method to the determination of total oxygen in oxidized oils in the presence of small amounts of sulfur contained in the oils. The method is the hydrogenation method of ter Meulen (7); it has enjoyed the best success of all the direct methods for oxygen, although some workers have reported difficulties with it, one of the latest being Gauthier (8).…”