Obtención de biodiésel mediante transesterificación de aceite de ricino y grasas animalesAprovechamiento energético de la glicerina como subproducto del proceso

Abstract

This doctoral dissertation was divided into four main sections: biodiesel production form animal fats, biodiesel production from castor oil, determination of biodiesel properties, and use of glycerine by means of steam reforming. The use of animal fats as raw material to produce biodiesel would suppose the revitalization of this waste. On the other hand, the castor oil plant can grow in marginal lands, shows easy adaptability and high oil yield. Several processes to obtain biodiesel were studied for both raw materials. They were acid and basic catalysis under conventional heating, in presence of microwave radiation and under subcritical methanol conditions. Moreover, a two-step process was tested for castor oil and animal fats. In the first case, the process consisted of two basic transesterification reactions in series. And, for animal fats, it consisted of acid esterification followed by basic transesterification. Biodiesel production cost was estimated for the most favorable conditions. Finally, biodiesel properties and its changes along storage time were evaluated. Considerable amounts of glycerine are generated by biodiesel industry. For this reason, its use to produce syngas or hydrogen by steam reforming was proposed. The studied processes were: steam reforming of glycerine, this process with CO2 abatement, catalytic steam reforming and catalytic steam reforming in presence of CO2 sorbent. The result was a gas stream rich in hydrogen.