Production of biodiesel from pork lard waste and characterization of its properties

The present work explores the potential of pork lard waste as a feedstock for the production of biodiesel. The production involved a unique pathway of reaction using Nitric Acid, an acidic catalyst rather than following the conventional method with a basic/alkali catalyst. The catalyst of choice helped the production to achieve maximum conversion of 92% (9.2g biodiesel/10g fat) by converting the undesired cholesterol in the fat to desired long-chain fatty acids. While achieving a high conversion, the amount of alcohol reagent consumed was recorded to be less than that of the conventional method. Soap, a hindering bi-product formed is also ruled out, unlike in the conventional method. The present work also voids out any hindrance in the yield due to FFA (Free Fatty Acids). The influence of operating conditions such as catalyst loading, alcohol to fat ratio, and reaction time were investigated. The presence of cholesterol in the feedstock and esters in the obtained biodiesel was confirmed through Gas Chromatography analysis. Biodiesel obtained was also tested for the physiochemical properties and was compared to that of the respective standards such as ASTM and IS. The results were found out to be matching to that of the standard range. Thus, from the findings of the present work a conclusion was drawn that the biodiesel produced from pork lard waste could be a promising supplementary fuel to the commercial diesel. Moreover, considering the amounts of reagents used, the explored method is more economically feasible compared to the conventional method where a basic catalyst is utilized. The finding from the current work also offers a new methodology to work with high ‘cholesterol-containing’ fats to produce biodiesel.