Abstract
Determination of inorganic sulfur compounds (H2S, SO2) with carboxylic acids by conductimetric titration in DMF (N, N-dimethylformamide) has been reported previously {C. Yoshimura, H. Hara, K. Tamura : This Journal, 18, 689 (1969)}.
This paper deals with the conductimetric titration of organic sulfur compounds (ethylmercaptane, thiophene, thiooxine, etc.) with carboxylic acids in nonaqueous media and its application to the determination of thiophene in benzene.
DMF solutions of sample and titrant were prepared, and from the results of titration in DMF, their reactive ratios were given as follows; thiophene:C6H5COOH=2 : 1 and 1: 1, and thiophenol : C6H5COOH=2 : 1 and 1: 1.
In the case of aminopolycarboxylic acids, various reactive ratios were obtained. Organic sulfur compounds (soluble in DMF) could be thus titrated with carboxylic acids, and thiophene in benzene was determined after an addition of a large amount, of DMF (about 10 times as much as benzene).
