Methylene Blue Active Substance Mistakable for ABS in Air and Waters

Abstract

Alkyl benzene sulfonate (ABS) was announced to be one of the air pollutants. In fact, it was found that Methylene Blue active substance (MBAS) was detected by Abbott's Methylene Blue method in alcohol extracts of air-dust. Examinations were carried out on the MBAS. Results showed that the MBAS was not due to ABS.An interesting fact was observed by the application of Methylene Blue-anionic surfactant complex on thin layer chromatography (TLC) with silica gel adsorbent : in case of a mixture of chloroform and ethanol (5 : 1) as a solvent, the Rƒ value of the surfactant complex was nearly zero, but the other MBAS (interferences), if present, migrated on the definite Rƒs, in case 99% ethanol as solvent the complex splits into its components and only the surfactant moved in accordance with its specified Rƒ.This fact was applied on colored chloroform-soluble substances obtained from waters by Abbott's method, as an examination method to check the presence of MBAS excluding ABS and to remove them. The proposed TLC-method was found to be an useful method for the determination of ABS in polluted waters and for examination of results obtained by Methylene Blue method.