title: Electrochemical determination of phenol using CTAB-functionalized montmorillonite electrode.
abstract: Montmorillonite calcium (MMT) was modified with cetyltrimethylammonium bromide (CTAB) via replacement of its inorganic exchangeable cations. The resulting CTAB-modified MMT (CTAB/MMT) was used to modify the carbon paste electrode (CPE). The electrochemical behaviours of phenol at the unmodified CPE, MMT-modified CPE and CTAB/MMT-modified CPE were examined. It was found that the oxidation signal of phenol was remarkably improved at the CTAB/MMT-modified CPE, which was attributed to the higher accumulation efficiency of CTAB/MMT. Based on this, a sensitive and convenient electrochemical method was proposed for the determination of phenol. The effect of supporting electrolyte on the oxidation of phenol was examined, and 0.1 mol l(-1) NaOH was finally employed. In addition, the influences of mass content of CTAB/MMT and accumulation time were also investigated. The optimal mass content of CTAB/MMT is 25%, and the accumulation time is 3 min. Under the optimized conditions, the oxidation peak current of phenol is proportional to its concentration over the range from 1.0 x 10(-7) to 3.0 x 10(-5) mol l(-1), and the limit of detection is estimated to be 6.0 x 10(-8) mol l(-1). Finally, the CTAB/MMT-modified CPE was successfully applied to determine phenol in water samples.
authors.affiliation: Key Laboratory of Biologic Resources Protection and Utilization of Hubei Province, Hubei Institute for Nationalities, Enshi, PR China.
authors.forename: Wensheng
authors.initials: W
authors.lastname: Huang
authors.forename: Dazhai
authors.initials: D
authors.lastname: Zhou
authors.forename: Xiaopeng
authors.initials: X
authors.lastname: Liu
authors.forename: Xiaojiang
authors.initials: X
authors.lastname: Zheng
mesh_terms: D001546:Bentonite / Q000737:chemistry*; D002244:Carbon / Q000737:chemistry; D000077286:Cetrimonium; D002593:Cetrimonium Compounds / Q000737:chemistry*; D055664:Electrochemical Techniques / Q000379:methods*; D004566:Electrodes; D019800:Phenol / Q000032:analysis*; D012680:Sensitivity and Specificity; D014867:Water / Q000737:chemistry
chemical_list: D002593:Cetrimonium Compounds; D014867:Water; D001546:Bentonite; D019800:Phenol; D002244:Carbon; D000077286:Cetrimonium