Spectrophotometric Determination of Aminophenol Isomers in Aqueous Solution using 1,2-Naphthoquinone-4-sulphonate Reagent

  • N. N. Habeb Chemistry Department, College of Education, Mosul University, Mosul, Iraq
  • T. N. Al-Sabha Chemistry Department, College of Education, Mosul University, Mosul, Iraq

Abstract

A spectrophotometric method was developed for the quantitative determination of aminophenol isomers. The method is based on their reaction with 1,2-Naphthoquinone-4-sulphonate (NQS) reagent in aqueous basic medium forming colored products with maximum absorption at wavelengths 488, 480 and 535 nm for o-, m- and p-aminophenol respectively. Beers law is obeyed over the concentration range of 0.2-10, 0.08-7.2 and 0.08-18 g ml-1 with molar absorptivity values of 5166.6 ,6613.6 and 7673.6 L mol-1 cm-1 for the above isomers, respectively. The average recovery was ranged between 99.14 % to 102.5 % and the precision was better than 4.0 %. The limit of detection was in between 0.0348 and 0.05188 g ml-1. The products are formed in ratio of 1:1 and the stability constants are 3.97107, 8.58105, 2.95105 L mol-1 for the above isomers, respectively. The method was applied successfully for the determination of oaminophenol in river, tap, spring and sea waters.

Published
Dec 1, 2011
How to Cite
HABEB, N. N.; AL-SABHA, T. N.. Spectrophotometric Determination of Aminophenol Isomers in Aqueous Solution using 1,2-Naphthoquinone-4-sulphonate Reagent. Pakistan Journal of Analytical & Environmental Chemistry, [S.l.], v. 12, n. 1 & 2, p. 8, dec. 2011. ISSN 2221-5255. Available at: <http://pjaec.pk/index.php/pjaec/article/view/164>. Date accessed: 22 sep. 2017.