Modification of montmorillonite with cationic surfactant and application in electrochemical determination of 4-chlorophenol.

Herein, montmorillonite calcium was exchanged with a cationic surfactant: cetyltrimethylammonium bromide (CTAB). The resulting CTAB-modified montmorillonite calcium (CTAB-MMT) shows higher accumulation efficiency to 4-chlorophenol compared with the unmodified MMT. At the CTAB-MMT-modified carbon paste electrode, the oxidation peak current of 4-chlorophenol remarkably increases. Based on this, a novel, sensitive and convenient electrochemical method was developed for the determination of 4-chlorophenol. The oxidation peak current of 4-chlorophenol is proportional to its concentration over the range from 5.0 x 10(-8) to 1.0 x 10(-5) mol L(-1). The limit of detection is evaluated to be 2.0 x 10(-8) mol L(-1) for 2 min accumulation. Finally this newly proposed method was successfully applied to determine 4-chlorophenol in water samples.