Optimization of Biodiesel Production Process from Restaurant Waste Frying Oils in the Presence of Homogeneous Catalyst

Background and Objective: Because of the importance of the role of energy in the world and nonrenewability of fossil fuels and caused environmental issues by these fuels in recent years, many studies have been conducted to find an appropriate alternative to fossil fuels in different countries of the world. Biofuels such as (biodiesel and bioethanol) have been introduced as one of the most desirable alternatives.The purpose of this study is investigation the production of biodiesel from waste frying oils in the presence of a homogeneous catalyst. Methods: This study is an experimental-laboratory. In this study, the impact of three parameters including reaction time (60,70 and 80 minutes), weight percent of catalyst (.5, 1 and 1.5 percent) and molar ratio of methanol to oil (3:1, 6:1 and 9:1) Was investigated at three levels. The biodiesel production efficiency was calculated using the produced biodiesel mass from the amount of consumed primary oil. Results: The maximum production efficiency of biodiesel in the presence of sodium hydroxide as homogeneous catalyst was obtained 86.6 ± 3.23%. Optimum conditions for the maximum efficiency were methanol to oil molar ratio of 6:1, weight percent of catalyst 1 and reaction time of 70 minutes. In this study the reaction temperature and mixing intensity were considered of 65 ° C and 500 rpm respectively. Conclusion: The waste frying oils of restaurants that are producing a lot in our country are a great source for biodiesel production and energy supply.