Characterization and Testing of KF/CaO Heterogeneous Catalyst for Biodiesel Production

573-580The application of heterogeneous catalyst in the production of biodiesel cannot only decline the costs of the separation process but also reduce the cost of biodiesel. The present study has emphasized on the performance evaluation of KF/CaO catalyst for biodiesel synthesis from nonedible Jatropha curcas oil (JCO). The synthesized catalyst was characterized through various analytical methods such as powder X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), CO2-temparature program desorption (CO2-TPD), scanning electron microscopy (SEM), energy dispersive X-ray (EDX) spectroscopy, BET surface area (SA) and thermo-gravimetric analysis (TGA). The novelty of this heterogeneous catalyst (KF/CaO) is its reuse without leaching of Ca2+. It was observed from experimental study that prepared catalyst reflects high efficiency towards catalytic transesterification activity. Furthermore, the catalyst has admirable stability, making it suitable for use as a solid base catalyst in the manufacture of biodiesel from Jatropha curcas oil with 5.5 percent free fatty acid (FFA). Reusability tests of the prepared catalyst validated that it could be reused up to four times without sacrificingample activity, thereby giving rise to a potentially relevant biodiesel production possibility

Silicon nitride/SiAlON ceramics —A review

36-45Advanced ceramic materials such as Si3N4 and SiAlON are reviewed here with particular reference to their synthesis, properties, and applications in various sectors such as transport and defense. It is noticed that synthesis by the simultaneous carbothermic reduction and nitridation (CTR) is relatively easy and economical. The products thus obtained by CTR, have unusual combination of unique properties, viz., high strength at higher temperature, chemical inertness, wear resistance, etc. , and therefore they are very much useful in high-tech areas. In addition, some of the leading manufacturers of Si3N4/SiAlON are listed in this paper. Ceramic whisker growth mechanism and its importance in improving the mechanical properties of ceramic matrix composites (CMCs) are also discussed. This paper is mainly intended to cover important properties like structural, mechanical, oxidation/corrosion and wear resistance of Si3N4 and SiAlON