High-Temperature Gas Burners for Microcombustion Methods of Ultimate Analysis

Abstract

Coil and ring gas burners are described which fulfill the requirements of the thermal decomposition method for the direct determination of oxygen in organic compounds. The coil burner is designed for pyrolyzing the sample at 900°to 1000°C .; however, it is capable of producing a temperature of 1300°t o 1350°C. inside the reaction tube. The ring burner is designed to provide a temperature of 1100°C. near the end of the furnace used for conversion of the pyrolysis products to carbon monoxide. These gas burners have also been found useful in other microcombustion methods of ultimate analysis. The burners, which utilize a mixture of propane gas and air, are inexpensive, heat and cool the reaction tube rapidly, and provide a uniform distribution of heat around the tube. INTHE thermal decomposition method for the direct determination of oxygen in organic compounds, first proposed by Schiitze (2), the substance is py'rolyzed in a clear quartz tube in a stream of pure nitrogen at a temperature of 900°to 1000°C.

Direct Semimicrodetermination of Oxygen in Organic Substances

“…which attacks and reduces the tube wall by slow dehydrogenation. In view of the wide variety• of reaction tube furnaces available for use in this work and their variation in constructional characteristics, devices suchas the nickel shield (Figure 2), ' or the special burner described by Aluise (1), should be used if low temperature zones are to be avoided. The existence of such zones can produce anomalous results (low or high, depending upon the nature of the sample), variable operating blanks, and extended analysis times.…”

“…who made the precision studies, many of the interference studies, and helped in the differential polarographic end-point studies; E. M. Kinderman, who helped with the pretreatment and interference studies and the early automatic titrations; W. W. Mills, who furnished the standards for the investigation; and Roy Ko and G. Meyer, who established the need for iron in the generation system. LITERATURE CITED (1) Carson, W. N., Jr., Anal. Chem., 25,226 (1953).…”