Schoniger combustion

The first step in determination of total sulfur in pulp by combustion/ion chromatography entails burning the pulp in a Schoniger combustion flask (Douek and Ing 1989). Combustion of the pulp in an oxygen atmosphere in a platinum boat oxidizes the sulfur to sulfate which dissolves in deionized water at the bottom of the flask. The presence of a few drops of hydrogen peroxide in the deionized water ensures that oxidation to sulfate is complete. 

SchOniger combustion flask 477, 478 seml-bleached pulps 71, 72, 73 Sephadex gels 360,487-489 silylation 290, 293-295, 337, 378,... 

There are several methods available to determine the amount of carbon-bonded fluorine. One of the earlier methods employed the Schoniger Combustion technique followed by thorium nitrate or cerous chloride titration using sodium alizarin sulfonate or murexide as the indicator (21). 

Miscellaneous Various Sulphur Schoniger combustion -potent 10 metric titration with Ba(C104)2 [101, 102]... 

Miscellaneous Various Chlorine, bromine, oriodine Schoniger combustion - potentiometric titration with Aq NO3 [103]... 

Miscellaneous Various Fluorine Schoniger combustion spectrophotometric evaluation of alizarin cerous nitrate complex at 610 nm [106]... 

Percolated water is prepared by percolating distilled water through a mixed resin hed containing Amberlite IR-120(H) and Amberlite IRA-400(OH). This water must he boiled immediately before use and should be used throughout during the Schoniger combustion stage of the analysis. 

Add to a 500 ml Schoniger combustion flask, 1 ml of 100 volume hydrogen peroxide and 10 ml of recently boiled-out distilled water. Add 0.1 ml each of methyl red and... 

Where T = Titration (ml) of sodium hydroxide after Schoniger combustion of sample extract. 

V = Volume (ml) of original extraction liquid represented by portion of ether extract taken for Schoniger combustion. 

In view of the evidence concerning the possible degradation of DLTDP during the analysis, it is desirable to apply the same treatment to the standard DLTDP calibration solutions as applied during the analysis of plastic extraction liquids of unknown DLTDP. This would cancel out errors in the analysis caused by partial degradation of DLTDP. To calibrate the procedure, various standard concentrations of DLTDP were made up in each of the extractants, which were then heated for 10 days at 60 °C. The aqueous extractants were then ether-extracted and the extracts used to calibrate the Schoniger combustion and the infrared procedures. 

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