What is Biodiesel?

"Made from an increasingly diverse mix of resources such as recycled cooking oil, soybean oil and animal fats, biodiesel is a renewable, clean-burning diesel replacement that can be used in existing diesel engines without modification. It is the nation’s first domestically produced, commercially available advanced biofuel."
https://www.biodiesel.org/what-is-biodiesel/biodiesel-basics

"Biodiesel is a domestically produced, renewable fuel that can be manufactured from vegetable oils, animal fats, or recycled restaurant grease for use in diesel vehicles or any equipment that operates on diesel fuel. Biodiesel's physical properties are similar to those of petroleum diesel."
https://afdc.energy.gov/fuels/biodiesel.html

"Biomass-based diesel fuels used as petroleum distillate fuel oil (diesel fuel and heating oil) include biodiesel and renewable diesel. They are both called biomass-based diesel fuels because they are mostly produced for use in diesel engines, but they can also be used as heating fuels. Both fuels are made from biomass or materials derived from biomass, but they differ in how they are produced and in their physical properties. Biodiesel meets the American Society for Testing and Materials (ASTM) specification ASTM D6751 and is approved for blending with petroleum distillate/diesel. Renewable diesel meets ASTM D975 specification for petroleum diesel, and it does not require blending with petroleum diesel for its use. Both fuels qualify for meeting the biofuels consumption levels required by the U.S. Renewable Fuel Standard Program."
https://www.eia.gov/energyexplained/biofuels/biodiesel.php

"Biodiesel production is a deceptively complex process, rather than a simple process at first sight, especially if you want to make quality biodiesel and a product that meets ASTM D 6751 specifications and not harm a diesel engine. The type of processes and equipment used to make the biodiesel is determined by the feedstocks you plan to use in producing the biodiesel. There are a number of processes and operating parameters that affect the transesterification reaction used to produce biodiesel and are feedstock—and other reactant-dependent."
https://www.sciencedirect.com/topics/engineering/biodiesel-production

"Usually derived from vegetable oils -- soy is very popular these days, but animal fats can also be used -- biodiesel is made through a chemical process called transesterification which essentially splits the oil into two parts: alkyl esters and glycerine; the esters are the fuel, while the leftover glycerine is often used to make soap and other beauty products. Both virgin and waste oil (often collected from restaurants) can be used in this process with equally good results. The fuel can be produced domestically, from seed to pump, and is non-toxic and biodegradable."
https://www.treehugger.com/biodiesel-environmental-impact-4858299

"Soybean farmers led the original development and now lead the continued growth of the biodiesel industry. Through the soy checkoff, research and promotion efforts help ensure biodiesel remains one of the most tested and widely used renewable fuels on the market.

In the U.S., biodiesel manufacturers rely on U.S. soybean oil as the primary feedstock for this renewable fuel. Biodiesel was the first domestically produced and commercially available fuel to meet the Environmental Protection Agency’s definition of an advanced biofuel."
https://www.unitedsoybean.org/topics/biodiesel/

"Bioenergy Australia estimates that biodiesel could cut emissions by over 85% compared to diesel"
https://www.rac.co.uk/drive/advice/know-how/what-is-biofuel-and-biodiesel/

"Biodiesel tends to cost more than petroleum diesel, and prices vary across the country"
https://fueleconomy.gov/feg/biodiesel.shtml

"The cost of producing biodiesel is approximately the same as the price of producing petroleum. Incentives provided by federal policies have helped keep market prices competitive. Federal low-sulfur diesel fuel standards have also given biodiesel a boost."
https://www.caranddriver.com/research/a31883731/biodiesel-vs-diesel/