Start
Jan 08, 2015 - 17:00
End
Jan 08, 2015 - 18:00
Venue
Room 149 Chemical Engg.
Event Type
Speaker
Rohidas Bhoi PhD Student Chemical Engineering IITB
Title
Process development studies for biodiesel synthesis.
Abstract : Biodiesel is produced from vegetable oils animal fats and acid oil using heterogeneous/homogeneous acid/ base catalyst. In the present work synthesis of biodiesel is carried out in three different type of reactor viz. fixed bed reactor batch reactor and microreactor. The process for the production of biodiesel can be intensified significantly by employing a heterogeneous catalyst. In the present work a heterogeneous catalyst ZnO/ZSM-5 is used that promotes both esterification and transesterification simultaneously. The synthesis of biodiesel was carried out in a fixed bed reactor using sunflower oil and jatropha oil. The catalyst was used in the form of cylindrical pellets having 6 mm ID and 8-10 mm length. The conversions higher than 90% were realized for both TG and FFA typically at 200 0C and molar ratio of 6:1 for a residence time of 40 gm cat/(ml/min). The transesterification of sunflower oil with methanol is investigated with homogeneous catalyst. It is a two phase reaction. The reaction was carried out in a batch reactor with independent stirring of both phases keeping interface flat. The intrinsic kinetics of the reaction is fast and limited by mass transfer. The progress of the reaction greatly depends on the speed of agitation and the interfacial area. Spontaneous emulsion was observed with sudden rise of interfacial area and reaction rate. It was observed that apart from agitation speed the changing composition of the phases plays an important role to reduce the interfacial tension that causes spontaneous emulsion. Transesterification of sunflower oil with methanol using homogeneous catalyst has been studied in three different types of microreactors.. Effects of temperature contact time and feed molar ratio on the conversion of triglyceride (TG) have been studied. In some cases conversion of TG is not found to change monotonically with change in flowrate. Flow patterns are observed using a high speed camera in an attempt to explain this seemingly unusual trend in some cases. The results from the experiments conducted in this study indicate that it is possible to get very high TG conversion (>95%) with residence time less than 2 minutes.