Photometric Analysis of Pentachlorophenol in Water by Extraction with Astrafloxin

• Published in: Journal of water chemistry and technology 2022-06, Vol.44 (3), p.169-174
• Main Authors: Kormosh, Zholt, Matskiv, Olena
• Format: Article
• Language: English
• Subjects: Absorbance; Absorption coefficient; Absorptivity; Analysis; Analytical Chemistry of Water; Aquatic Pollution; Aromatic compounds; Aromatic hydrocarbons; Bottom sediments; Distribution; Dyes; Earth and Environmental Science; Environment; Homogeneity; Industrial Chemistry/Chemical Engineering; Linear equations; Mathematical analysis; Pentachlorophenol; Photometry; Sediments; Spectrophotometry; Stoichiometry; Toluene; Waste Water Technology; Water Industry/Water Technologies; Water Management; Water Pollution Control; Water Quality/Water Pollution
• ISSN: 1063-455X; 1934-936X
• DOI: 10.3103/S1063455X22030079

Pentachlorophenol (PCP) and astrafloxin FF (AF), a polymethine dye, were shown to form an ionic associate (IA), which could be rather perfectly extracted by different aromatic hydrocarbons. A maximum extraction of the ionic associate was attained at pH 8–12, being in quite a good agreement with the data obtained by calculating the distribution diagrams of corresponding dye and PCP forms. The distribution diagrams of these forms were calculated and constructed by using the MarvinScetch software. The effect of the dye concentration on the absorbance of the toluene extracts of PCP–AF ionic associates was studied. The PCP recovery attained a maximum at a dye concentration of (1.6–2.8) × 10 –4 M. Extraction equilibrium was established for 50–60 s. The stoichiometry of the PCP–AF ionic associate was studied by the spectrophotometric methods of isomolar series and equilibrium shift, and the ratio of components was 1 : 1. The scheme of the formation and extraction of this ionic associate was proposed. The conventional molar absorption coefficient of the ionic associate was 1.2 × 10 5 . The calibration curve of the extract absorbance as a function of the PCP concentration could be described by the linear equation А = 0.0121 + 0.0622 c within a PCP concentration range of 1.2–60.3 μg/cm 3 . The PCP detection limit calculated by the 3 s -criterion ( n = 5, Р = 0.95) was 1.08 μg/cm 3 . The intralaboratory disperancy of the calibrating plot for PCP analysis with astrafloxin was estimated by the Cochran test G . The calculated Cochran test ( n = 5, P = 0.95) was smaller than its tabular value: G calcd = 0.27 < G tab = 0.64 to argue for variance homogeneity. A method for the extraction photometric analysis of pentachlorophenol in water and bottom sediments was developed.