Development of Flow Injection Spectrophotometric Method for 1-Napthylthiourea Using Sodium Nitrite and Sulphanilic Acid Diazotization Reaction

Figure 3

Optimization of reagents concentration. (a) Sulphanilic acid, (b) sodium nitrite, (c) sodium hydroxide, and (d) ethanol. Experimental conditions: flow rate 0.5 mL/min, sample loop volume 300 µL, reaction coil-I length 200 cm, reaction coil-II length 150 cm, wavelength 495 nm, temperature 30°C, and ANTU concentration 10 mg/L.

(a)

(b)

(c)

(d)