Polyaniline film was prepared by using the repeated potential cycling technique in an acidic solution at the surface of glassy carbon electrode. Then transition metal ions of Ni and Cu were incorporated to the polymer...Polyaniline film was prepared by using the repeated potential cycling technique in an acidic solution at the surface of glassy carbon electrode. Then transition metal ions of Ni and Cu were incorporated to the polymer by immersion of the modified electrode. A comparative study of the electrocatalytic oxidation of methanol is made in NaOH, on Ni and Cu on polyaniline film covered glassy carbon electrode (Ni-PANI-GC, Cu-PANI-GC) at 25℃. Catalytic activity for the oxidation of methanol was studied by using cyclic voltammetry.展开更多
This work aims to characterize and determine the dehydroxylation enthalpy variations of two natural Moroccan clays from the Nador region (denoted K1) and the Settat region (denoted by K2). The variations of dissolutio...This work aims to characterize and determine the dehydroxylation enthalpy variations of two natural Moroccan clays from the Nador region (denoted K1) and the Settat region (denoted by K2). The variations of dissolution enthalpies were determined by dissolving clays in hydrofluoric acid. They have a minimum value for dehydroxylation of clays made between 600°C and 700°C. The analysis of the two clays shows that they consist of kaolinite in significant proportion. The optimum calcination parameters, for which dehydroxylation is total, are 700°C with a heating time of 6 H. The conversion of the kaolinite to metakaolinite was confirmed by IR analyses of the starting and thermally treated kaolin samples. The result confirms previous observations about obtaining metakaolinite with optimum reactivity when hydrated with calcium hydroxide as chemical activator.展开更多
文摘Polyaniline film was prepared by using the repeated potential cycling technique in an acidic solution at the surface of glassy carbon electrode. Then transition metal ions of Ni and Cu were incorporated to the polymer by immersion of the modified electrode. A comparative study of the electrocatalytic oxidation of methanol is made in NaOH, on Ni and Cu on polyaniline film covered glassy carbon electrode (Ni-PANI-GC, Cu-PANI-GC) at 25℃. Catalytic activity for the oxidation of methanol was studied by using cyclic voltammetry.
文摘This work aims to characterize and determine the dehydroxylation enthalpy variations of two natural Moroccan clays from the Nador region (denoted K1) and the Settat region (denoted by K2). The variations of dissolution enthalpies were determined by dissolving clays in hydrofluoric acid. They have a minimum value for dehydroxylation of clays made between 600°C and 700°C. The analysis of the two clays shows that they consist of kaolinite in significant proportion. The optimum calcination parameters, for which dehydroxylation is total, are 700°C with a heating time of 6 H. The conversion of the kaolinite to metakaolinite was confirmed by IR analyses of the starting and thermally treated kaolin samples. The result confirms previous observations about obtaining metakaolinite with optimum reactivity when hydrated with calcium hydroxide as chemical activator.
