Quickly,
How can Biodiesel be a lubricant and a solvent at the same time????

 

Easily - just think of glycerin (soap)

 

Nice idea, but I don't think that glycerin is soap. Glycerin may be found in soap, but it is often taken out to produce moisturizers which are more profitable -- especially as a cure to the now drying or non-moisturizing soap.

A solvent is just a liquid, such as water, that dissolves another substance. A solvent can be thick or thin like dish soap or acetone. Dish soap is actually a detergent, but it cleans just as a solvent can. A lubricant reduces friction between two surfaces. It seems sensical that a thicker, or most viscous, liquid would yeild a better thin film that separates the surfaces thus being a better lubricant. B100 has a higher viscosity index (resistance to flow) of 5.7 over Diesel #2 at 3.0.