Thomas - S c h ö n i g e r LOW PRESSURE, ALL GLASS C O M B U S T I O N APPARATUS

• For determination of halogens, sulfur, phosphorus, traces of metals, etc., in organic materials

• End products free from metal contaminants

• Rapid, simple and inexpensive

a simplified technique for catalytic combustion of organic materials in oxygen

F o r the rapid de terminat ion of halogens, sulfur, phosphorus , t races of metals , etc. , in organic substances b y simple combust ion in oxygen. N o elaborate equ ipment is required, negligible pressure is produced and t h e combust ion prod­ucts are free from metal l ic con taminan t s .

The procedure simply converts organic materials into soluble combustion products, which are then analyzed for chlorine, bromine, iodine, fluorine and sulfur by usual inorganic gravimetric or volumetric methods.

Consisting of a heavy wall, conical flask of boro-silicate glass, with deep, bell-shape flaring lip and elongated interchangeable ground glass stopper with attached U-shape platinum wire gauze sample carrier, and small, specially cut, unsized low ash paper sheets which serve as holders for the sample.

In use, the sample is wrapped and folded in the paper with the narrow tail extending for ignition. Sample is then placed in the platinum carrier and the flask is charged with a small amount of absorb­ing liquid as required for the specific reaction and

with free-flowing oxygen. The paper tail is then ignited; the stopper with flaming sample is seated in the flask and flask then inverted a t an angle. The catalytic combustion proceeds a t high tem­peratures and the combustion products are ab­sorbed in the liquid, which forms a seal around the stopper. After cooling, the inside surfaces of the flask and stopper are thoroughly rinsed. Titrations can then be made directly in the flask.

Due to the inherent fragility of glass in the presence of reduced pressure, general safety regula­tions should be followed, such as the use of shield, goggles, etc.

Results compare favorably, i.e., within ±0 .3%, with conventional combustion or decomposition methods. The method has been used extensively for analysis of the above elements but, because of the low cost, time and space saving features, is finding wide use for other substances which undergo complete combustion.

See Wolfgang Schoniger, Mikrochimica Acta, 1955, Heft 1, pp. 123-129; and ibid. 1956, Heft 1-6, pp. 869-876. See also Kenneth D. Fleischer et al, Analytical Chemistry, Vol. 30, No. 1 (Jan., 1958), pp. 152-153, and Ihor Lysyj and John E. Zarembo, Analytical Chemistry, Vol. 30, No. 3 (Mar., 1958), pp. U28-U30.

6470-E. Combustion Apparatus, Thomas-Schoniger (Schoniger Flask), as above described, 300 ml capacity, for samples up to 10 mg. With No. 34/28 standard taper stopper and platinum wire gauze sample carrier weighing approximately 1.5 grams, 100 Paper Sample Holders and directions for use 2 8.35

6470-G. Ditto, similar to 6470-E but with 500 ml flask, for samples up to 1 00 mg 29 .00

6 4 7 1 - F . P a p e r S a m p l e H o l d e r , only, an unsized, low ash paper, die-cut to facilitate wrapping, folding and igniting samples. Per l O O 7 5

Thor in Ind ica to r , for use with above in determination of sulfates. P e r 5 g r a m b a t t l e 4 . 9 5

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