【Abstract】 Benzalkonium bromide is a high-efficiency algaecide.Its concentration in seawater was measured by the method of spectrophotometer. The results indicated that the deposition appeared if the concentration of benzalkonium bromide in seawater was more than 50mg·L -1,and affected the detection of benzalkonium bromide.But,there was a good linear relationship between concentration and absorbance when the concentration was lower than 50mg·L -1 (R 2=0.9996). Therefore,spectrophotometer could be used to detect benzalkonium bromide in seawater.更多还原