Understanding Biobased Carbon Content Measurement

  • Biobased carbon testing is able to distinguish biobased from non-biobased products
  • The terms biobased and non-biobased are applicable to carbon-containing products
  • A product’s biobased carbon content is reported as a fraction of total organic carbon content (TOC) and not on its weight according to ASTM D6866
  • A product’s biobased carbon content can be reported as a fraction of total carbon content (TC) according to other standardized methods such as ISO 16620-2 and CEN 16640.

Here are some definitions to clarify the concepts:

biomassBIOBASED – Materials that are derived in whole or in part from biomass resources are biobased. Biomass resources are organic materials that are available on a renewable or recurring basis such as crop residues, wood residues, grasses, and aquatic plants. Corn ethanol is a well-known example of a biobased material derived from biomass resources.

BIOBASED PRODUCT – Any product that contains some amount of biobased material within it is technically a biobased product. The term is typically applied only to materials containing carbon.

NON-BIOBASED PRODUCT – Any product that does not contain any biobased materials in it is a non-biobased product, but the term is typically applied only to materials containing carbon. Products made entirely from petrochemical resources are referred to as non-biobased products. Glass, however, is not generally referred to as non-biobased material since it doesn’t contain any carbon.

PERCENT BIOBASED CARBON CONTENT – This is a measure of the amount of biomass-derived carbon in a product as compared to its total organic carbon content (Biobased carbon to TOC)​ per ASTM D6866. Other analytical standard methods such as EN 16640 and ISO 16620-2 allow biobased results to be reported as a fraction of total carbon (TC). Both have become acceptable ways of measuring biobased carbon content.

Biobased Content Measurements

The emerging biobased manufacturing industry is producing large quantities of products that contain mixtures of both biobased materials and petroleum-derived materials. “Percent biobased” is a measure of the amount of biobased carbon in the product as compared to the sum of biobased and petroleum-based carbon in the product. A percent biobased value of 75% would mean that of all the carbon in the product, 75% of it is biobased and 25% is petroleum based.1

The purpose of a biobased content measurement is to determine how much of the carbon within a biobased product is derived from biomass. The value represents a measure of how much biobased material a company is using to manufacture its products relative to the more readily available and less expensive petroleum-based alternatives.

1. Schonhofer, Franze. 14C in Austrian Wine and Vinegar. RADIOCARBON, VOL. 34, No. 3, 1992, P. 768-7711.

Suggested Readings:

Carbon 14 Analysis

What are Bioplastics?