Papers by Keyword: Peptizer

Abstract: The alumina sol with high content of Al₂O₃ was prepared by peptizing aluminum hydroxide powder. The properties of the alumina sol were characterized by Fourier transform-infrared (FT-IR) spectrum, zeta potential analyzer, X-ray diffraction (XRD) and Transmission electron microscope (TEM). The results show that the sol with high content of Al₂O₃ can be easily prepared by peptizing the soluble aluminum hydroxide powder, the smaller of the size of aluminum hydroxide powder, the higher of the aluminum content of the alumina sol. Two-step peptization process is optimum, the effect of peptization aluminum hydroxide powder using AlCl₃ :HCl=1:4 solution as peptizer is best, the alumina sol sample with pH value of 2.5 and alumina content 11% had good stability. A great application potential of the high alumina content sol has been displayed in preparing FCC catalysts.

Abstract: Nafion-clay nanocomposite membrane has been prepared by dispersing unmodified and acid activated Laponite XLS in Nafion 20% dispersion. The resulting membranes possess better proton conductivity and mechanical strength as compared to the virgin membrane. Acid activation of the nanoclay leads to the in-situ generation of H₃PO₄ by the hydrolysis of the peptizer present on the surface of the nanoclay. The in-situ generated H₃PO₄ helps in improving all the technical properties of the nanocomposite including the water uptake and proton conductivity of the nanocomposite, containing acid activated clay compared to the nanocomposite, containing unmodified clay. The maximum proton conductivity of 270.2 mS/cm is achieved at 110 °C for the nanocomposite membrane containing 3% acid-activated Laponite compared to 136.2 mS/cm for the virgin Nafion. Keywords: Nafion, clay, nanocomposite, peptizer, polymer electrolyte membrane fuel cell (FEMFC), proton conductivity, membrane