Production of Sustainable Diesel via Decarboxylation of Palm Stearin Basic Soaps (original) (raw)

Production of sustainable diesel was conducted via hydrogen-free decarboxylation of palm stearin basic soaps. Metal soaps are alkaline earth and transition metal salts combined with carboxylic acids with 7 to 22 carbon atoms. Stearin basic soaps were prepared by direct reaction of palm stearin and mixed metal (Ca, Mg, and Zn) hydroxides. The stearin basic soaps were decarboxylated at 370 °C for 5 h to produce liquid crude bio-hydrocarbon, also known as sustainable diesel. The stearin basic soaps were characterized by FTIR and TGA, and the resulted liquid bio-hydrocarbons were analyzed by GC equipped with FID. The hydroxyl band at 3678 cm-1 observed from Fourier transform infrared (FTIR) spectroscopy indicated that the Ca/Mg/Zn ions was associated with the-OH ions in the compounds. This proved that the soaps produced from this work was basic metal soaps. The thermal stability of the soaps was examined up to 1000 °C and the decomposition of stearin basic soaps was observed in the range of 300 to 500 °C. The metal contained in the basic soaps affected their thermal characteristics. Liquid crude bio-hydrocarbon with carbon chain length between 8-20 have been obtained from decarboxylation of stearin basic soaps. In this study, the decarboxylation of stearin basic soaps resulted in sustainable diesel as the main product. This promising process is expected to open plethora opportunities in the production of sustainable diesel.