Unlocking the potential of agricultural waste as biochar for sustainable biodiesel production: A comprehensive review

Overexploitation of resources that cannot be replenished is resulting in the reduction of energy supplies. Renewable energy that applies clean technology is in high demand these days. One of the renewable energies that continues to be developed today is biodiesel. Biodiesel is an alternative fuel produced from vegetable oil or animal fat. Nevertheless, there are still challenges in biodiesel production, including elevated production expenses and adverse effects on the environment. One solution to overcome these problems is to use biochar from agricultural waste as a catalyst during biodiesel production. The use of biochar can increase the efficiency of biodiesel production and create more environmentally friendly energy. The reason for utilizing agricultural waste as biochar is also because of its abundant availability and underutilization. As a result, a bibliometric analysis using VOSviewer was conducted to examine the utilization of agricultural waste as biochar in biodiesel production. Based on the Scopus database with data retrieval in the range of 2009 until March 12, 2024 there are 303 documents that discuss biochar and its application in biodiesel production. The importance of the findings from bibliometric analysis is that the author can see research trends, collaboration between researchers, and contributions from various institutions in the field. Thus, it makes it easier for the author to identify research gaps so that it becomes a strong basis for the author to compile a comprehensive and informative literature review on the utilization of agricultural waste as biochar in biodiesel production.