A comprehensive review on performance, combustion and emissions of ternary and quaternary biodiesel/diesel blends

Global dependency and exhaustive usage of fossil fuels is leading to depletion of fossil fuel energy. The exponential rise in energy demand is an alarming sign; and added to that, emission generation, from burning of fossil fuel, has caused adverse effect on the environment. This paves the way in harvesting renewable energy options for a futuristic clean and healthy environment. The potentiality of biodiesel as an alternate energy option is well explored in past couple of decades. However with biodiesel, NO_x emissions as well as performance of engine from biodiesel is reported to be inferior to that of diesel owing to their inferior physical properties like density and viscosity. The mixture of biodiesels and different types of alcohols neutralizes the inferior property of blends. Ternary or quaternary blends of biodiesel have reported positive engine results. Initially, detailed study of different types of binary blends with respect to performance and emissions is done, trying to identify the research gap with the usage of binary mixture. The paper then dives into detailed study of ternary and quaternary blends with respect to performance, emission and combustion characteristics, trying to highlight different research outcomes.