Toward the Standardization of Biochar Analysis: The COST Action TD1107 Interlaboratory Comparison

Area of Science:

• Environmental Science
• Agronomy
• Analytical Chemistry

Background:

• Biochar, derived from organic residue pyrolysis, is a valuable soil amendment.
• Current analytical methods for biochar characterization lack standardization, hindering data comparability.

Purpose of the Study:

• To assess the reproducibility of physical-chemical analyses for different biochar types.
• To identify key areas for method harmonization in biochar analysis.

Main Methods:

• An interlaboratory comparison involving 22 labs from 12 countries.
• Analysis of three distinct biochar samples for 38 physical-chemical parameters using preferred laboratory methods.
• Data evaluation using specialized interlaboratory testing software.

Main Results:

• Intralaboratory repeatability for biochar analysis was generally good.
• Interlaboratory reproducibility was largely insufficient, with high standard deviations for many parameters.
• Significant variability was observed in the analysis of elements, heavy metals, and surface area.

Conclusions:

• Existing biochar analytical methods require urgent optimization and standardization.
• Harmonized methods are crucial for reliable biochar data and effective soil amendment applications.
• This work provides a foundation for improving the comparability and accuracy of future biochar research.