Effect of Feedstock on PAHs in BiocharWith regards to feedstock, their differences in chemical compositions and structures can influence the formation and distribution of PAHs during the pyrolysis process. For example, biochar produced from wood feedstocks is often found to contain high levels of Benzo[a]pyrene, a highly toxic and carcinogenic PAH. This is because wood contains high levels of lignin, a complex polymer that can break down during pyrolysis to form PAHs such as Benzo[a]pyrene. Additionally, wood feedstocks tend to have a higher carbon content than other feedstocks, which can result in higher temperatures during pyrolysis and greater production of PAHs.
Effect of Pyrolysis Conditions on PAH LevelsTemperature is one of the most important factors in determining the types and amount of PAHs in biochar. Generally, higher pyrolysis temperatures lead to greater production of PAHs, including more toxic and carcinogenic forms such as benzo[a]pyrene and indeno[1,2,3-cd]pyrene. This is because high temperatures can break down complex organic molecules into simpler ones, including PAHs, and can promote reactions that favour their formation.
Main PAHs in BiocharSome of the main PAHs found in biochar include:
Types of PAHs Determined
Checking PAH Levels Against Threshold Values
Understanding Links Between Process, Feedstock and PAH LevelsIf you are currently producing a range of different from biochars covering different feedstocks and/or process conditions then we can help in screening these biochar samples for their PAH contents and compositions. We can then use data analysis tools to look for trends and correlations across the dataset. This can lead to greater understanding on what factors are most important, according to your particular conditions, with regards to PAH levels in biochar. From this we can provide guidance on how conditions can be optimised for reduced PAH concentrations, whilst also considering other factors such as target biochar yields and composition. Such data can feed into our technoecomomic analyses of biochar production scenarios.
Exploring Strategies to Reduce PAH Levels in BiocharThere are a number of different strategies that we at Celignis can test to reduce the levels of PAHs in your biochar samples. For example, we can wash or leach the biochar (using water or other solvents). This treatment can potentially remove any remaining ash or soluble organic compounds that may contain PAHs.
Our Biomass Detective! Designs, tests, optimizes and validates robust analytical methods for properties of relevance to the various biochar market applications.
PhD (Analytical Chemistry)
Dreamer and achiever. Took Celignis from a concept in a research project to being the bioeconomy's premier provider of analytical and bioprocessing expertise.