Temperature programmed desorption of normal alkanes from silicalite-1

Abstract

Temperature programmed desorption (TPD) of n-alkanes, ranging from n-hexane to n-hexadecane, from silicalite-1, was conducted between ambient temperature and 500°C on a thermogravimetric (TG) balance at heating rates of 3, 6 and 10 C° min⁻¹. The derivative TG curves all showed two distinctive peaks. An inflection point in the TG profiles was found at about four molecules per unit cell in all cases except hexadecane, which occurred at 1.92 molecules per unit cell. The saturation adsorption volumes of all sorbates was close to the theoretical value of ∼0.19 ml g⁻¹.