Palm acid oil (PAO) is a non-edible lipid byproduct generated during the refining of crude palm oil. After discharge, PAO is typically stored for extended periods in open ponds, where it undergoes phase separation into aqueous and oil fractions. The separated oil fraction, referred to as palm acid oil, is characterized by a high acid value and currently has very limited applications, primarily confined to fertilizer production and soap manufacturing.

In this study, we aim to chemically convert palm acid oil into second-generation biodiesel fuel (BDF). Catalytic processes are employed for this conversion; however, careful selection of catalyst systems and optimization of reaction conditions are essential to effectively process such highly acidic and degraded feedstocks.

By developing a relatively simple and robust upgrading strategy for these underutilized waste oils, this work seeks to add value to palm acid oil and contribute to the discovery and utilization of new sustainable energy resources.

Alkali foots, derived from vegetable oils such as soybean oil, is a non-edible byproduct generated during the refining process of edible oils. In its original form, alkali foots has limited economic value and is not suitable for direct use as a fuel feedstock.

Although alkali foots and palm acid oil share the common feature of being byproducts discharged from edible oil refining processes, their chemical compositions differ significantly, particularly in terms of fatty acid distribution and impurity content.

Therefore, in this study, we also focus on alkali foots as a distinct waste lipid feedstock and aim to convert it into second-generation biodiesel fuel (BDF) through the development of an appropriate upgrading process tailored to its unique characteristics.