UV-spectrophotometric Determination of Quaternary Ammonium Salt in Seawater

A method for the determination of quaternary ammonium salt in seawater by UV-spectrophotometry was proposed.The absorption maximum at the wavelength of 263 nm was chosen by comparing UV spectra of seawater of different concentrations.Linear relationships between values of absorbance and mass concentration of quaternary ammonium salts in distilled water and seawater obtained were in ranges within 100 and 50 mg·L-1 respectively.Detection limit (3S/N) of the method was found to be 3.205 mg·L-1.The average recovery found was 94.95%,with RSD (n=5) of 1.9%.