Method and apparatus for analysis of gases for sulfur dioxide
Abstract
Abstract SULFUR DIOXIDE IN GAS MIXTURES IS DETERMINED BY ABSORBING THE SULFUR DIOXIDE IN AN ALKALINE SOLUTION CONTAINING A P-AMINOPHENYL-AZOBENZENE DYE, E.G., P-(P-AMINOPHENYLAZOBENZENE) SULFONIC ACID SALT, THEN REACTING WITH AN ACIDIC SOLUTION CONTAINING FORMALDEHYDE TO FORM THE MORE HIGHLY COLORED N-METBYL SULFONIC ACID DERIVATIVE OF THE DYE AND SPECTRALLY MEASURING THE DYE-DERIVATIVE SOLUTION TO DETERMINE THE AMOUNT OF SULFUR DIOXIDE. THE METHOD IS HIGHLY SUITABLE FOR A APPARATUS FOR THE CONTINUOUS ANALYSIS OF AIR, AS IN AIR POLLUTION CONTROL, BY PROVIDING PUMPING, METERING AND MIXING OF THE GAS AND REGENT STREAMS IN THE PROPER SEQUENCE AND PHOTOMETRIC SCANNING OF THE RESULTANT SOLUTION.
Inventors
- 👤 Ferdinand Schulze
Bibliographic Details
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