Synthesis of methyl esters from Hippophae rhamnoides via pilot scale hydrodynamic cavitation intensification reactor

Abstract

The current research demonstrates the capability of hydrodynamic cavitation (HC) for the manufacture of ester sourcing Hippophae rhamnoides (HiRO) seed oil, which is non-edible in nature. According to the authors' best knowledge, the HC pilot developed assembly has not been put to use in any research pertaining to the manufacturing of biodiesel from HiRO triglycerides. The vast majority of the research indicates that optimising the system for the production of biodiesel based on a particular criterion, such as yield, can lead to only one portion of the research. In order to achieve maximum efficiency in the transesterification reaction, it is necessary to optimise not only the amount of output but also the cavitational parameters. The process of transesterification was initiated to overcome mass transfer resistance. In a pilot HC reactor, four novel geometries (orifices disk) cavities were explored. These cavities were helped along by a double diaphragm pump. It was shown that the mass transfer barrier between immiscible reactants can be decreased by increasing the interfacial area, and this effect was observed during the transesterification reaction, which is characterised by significant turbulence induced by cavitating bubbles. This was accomplished by increasing the surface area of the interface between the reactants. When compared to mechanical stirring, using an orifice plate with 21 holes that were 1 mm in diameter resulted in an eightfold increase in yield efficiency and a sixfold reduction in response reaction time at 2 bar inlet pressure. Utilising the hydrodynamic cavitation contributes to the procedure's reduced impact on the natural environment. In conclusion, the Hippophae rhamnoides oil methyl ester (HiROM) that was produced through the process of hydrodynamic cavitation was demonstrated to be both time and energy efficient. The characteristics of the methyl ester that was synthesised were in accordance with the requirements of both EN14214 and ASTM D6751.