Optimization of biodiesel production process for mixed nonedible oil (processed dairy waste, mahua oil, and castor oil) using response surface methodology

The fossil fuel-based energy supply represents dominant role in the developing countries like India. The extensive utilization of fuel in the industrial sector and transportation sector brings down the available fuel resources and also ensues environmental and health issues. Biodiesel is one of the major replacements for fossil fuel since it is renewable and green fuel. The current study perceives from futuristic notion and that has resulted in a mixture of nonedible oil feedstock in the use of biodiesel production by mixing castor oil (CO), mahua oil (MO), processed dairy waste (PWD) in equal volume. Five-level three-parameter design of experiment is proposed to optimize transesterification reaction parameters to achieve higher biodiesel yield (fatty acid methyl ester (FAME) conversion). The response surface methodology (RSM) based on central composite design (CCD) was used to predict optimal transesterification reaction parameters such as percentage of catalyst utilization, reaction temperature, and methanol-to-oil molar ratio. Based on the RSM-CCD result, the optimum transesterification reaction parameters of the proposed mixed oil were found to be 2.82 wt% of catalyst utilization, 63.93°C reaction temperature, and 7.86:1 methanol-to-oil molar ratio with maximum yield of 95.9135% and experimentally 94.0%. The fuel properties were measured as per ASTM D6751 standards and results disclosed that the prepared nonedible mixed oil is an effective feedstock for biodiesel production. This research work aimed to dwindle the dependency on crude oil and thereby ameliorating the energy security in a constructive and eco-friendly method. Hence, this work also reports the biodiesel production cost from the proposed novel mixed nonedible oil.