Simultaneous determination of volatile phenol, cyanide, anionic surfactant and ammonia nitrogen in drinking, ground and surface water and in wastewater applying continuous flow analyzer

Abstract

Abstract The present study aimed to develop a method for the simultaneous determination of volatile phenol, cyanide, anionic surfactant, and ammonia nitrogen in drinking, ground and surface water, as well as in wastewater, using a continuous flow analyzer. Using on-line distillation, the distillate reacts with 4-aminoantipyrine in the presence of basic potassium ferricyanide, and the amount of volatile phenol is assessed using spectrophotometry. The distillate combines with chloramine-T and then with isonicotinic acid pyrazolone to generate blue chemicals through on-line distillation. The amount of cyanide is measured using spectrophotometry and extracted on-line, the amount of anionic surfactants was measured using methylene blue spectrophotometry and extracted on-line, and ammonia is reacting with salicylate and chlorine from dichloroisocyanuric acid to produce indophenol blue at 37°C in an alkaline environment and measured at 660 nm. The relative standard deviations were 0.75%~ 2.80% and 0.36% ~ 2.26%, respectively, and the recoveries were 98% ~ 103.6% and 101% ~ 102% when the mass concentration of volatile phenol and cyanide is 2 µg/L ~ 100 µg/L, the linear correlation coefficients are greater than or equal to 0.9999, and the detection limits are 1.2 µg/L and 0.9 µg/L, respectively. The relative standard deviations were 0.27% ~ 0.96% and 0.33% ~ 3.13%, and the recoveries were 94.3% ~ 107.0% and 98.0% ~ 101.7%. The mass concentration of anionic surfactant and ammonia nitrogen is 10 µg/L ~ 1000 µg/L, the linear correlation coefficients are 0.9995 and 0.9999, and the detection limits are 10.7 µg/L and 7.3 µg/L, respectively. This approach saves time and labor, has a lower detection limit, higher precision and accuracy, less contamination, and is more appropriate for the analysis and determination of large amounts of samples. When compared to the national standard method, the difference was not statistically significant.