Enhancing Oxidation Stability Of Biodiesel Using Essential Oil As Antioxidant

Abstract

The fast depletion of petroleum resources has drawn every nation to look for renewable alternatives to petroleum Biodiesel is a renewable fuel which is used in Diesel engines It is produced from vegetable oils edible and non edible used cooking oils and animal fats through a chemical process called transesterification Compared to petroleum diesel biodiesel has many advantages that include higher cetane number higher flash point better lubricity free from sulphur ecofriendly renewable and biodegradable However the disadvantages are its lower oxidation stability its higher viscosity and higher oxides of nitrogen emission when it is used as fuel in Diesel engines In this experimental work the suitability of four essential oils viz clove bud oil cinnamon leaf oil thyme oil and oregano oil for improving the oxidation stability of biodiesel produced from Pongamia pinnata oil has been investigated Oxidation stability of the biodiesel refers to the propensity of the biodiesel to undergo autoxidation in the presence of oxygen at ambient temperature In this study Rancimat method was used to determine the oxidation stability of biodiesel Ranicmat method is an accelerated test procedure wherein the autoxidation of the biodiesel is accelerated by maintaining the biodiesel sample at 110 C and with constant supply of air at 10 Lh In Rancimat method the induction period of the biodiesel is determined which is the measure of oxidation stability of biodiesel Induction period is the time period after which the biodiesel undergoes oxidation at a rapid rate Higher the induction period higher is the oxidation stability of biodiesel and vice versa Biodiesel with lower oxidation stability undergoes degradation rapidly under storage newline