Iowa-based biodiesel producer Renewable Energy Group has released a report that looks at a wide variety of biodiesel feedstocks and the characteristics of both that feedstock and the fuel produced from it.

In the “Feedstock and Biodiesel Characteristics Report,” a first-of-its-kind of publication, REG, in cooperation with the Iowa Power Fund Board and the Iowa Office of Energy Independence, evaluated 36 biodiesel feedstocks and produced fuel from 34 of them:

These feedstocks varied from traditional fats and oils to novel feedstocks from around the world…

Each feedstock was tested for the following characteristics: moisture, free fatty acid, kinematic viscosity, FAC color, saponification value, moisture and volatile matter, insoluble impurities, unsaponifiable matter, MIU, oxidation stability, sulfur, phosphorous, calcium, and magnesium. If a feedstock exceeded 10 ppm phosphorous, 5 ppm calcium and magnesium, it was pretreated using the phosphoric acid procedure and dried. Feedstocks having free fatty acid in excess of 0.5 wt % were esterified using Amberlyst BD 20. The feedstocks were transesterified using identical reaction conditions and production protocols. Each biodiesel was characterized according to the American Society for Testing and Materials (ASTM) D6751 and other properties. These characteristics were: cloud point, cold filter plugging point, cold soak filtration, fatty acid profile, relative density, kinematic viscosity, sulfated ash, carbon residue, water and sediment, visual inspection, free and total glycerin, flash point, copper corrosion, phosphorous, calcium, magnesium, total acid number, moisture, sulfur, oxidation stability, and FTIR.

What makes the project so unique is that all of the wide range of feedstocks were pretreated, esterified, and transesterified using the same procedures and conditions to allow for uniform comparisons of critical fuel properties.

You can read the report for yourself here.