Hydropyrolysis and Biochar Persistence
Hydropyrolysis has been developed to quantify the fraction of carbon in biochars that will persist in soils for over 1,000 years.
Biochar Production
Biochar is primarily supplied by industrial partners producing at high volume from virgin wood feedstocks, however the project also includes biochar from smaller-scale manufacturers and using alternative feedstocks. Our extensive field trial programme will require upwards of 200 tonnes of biochar from our partners, which will satisfy stringent voluntary standards, including the European Biochar Certificate, for safe concentrations of heavy metals and polycyclic aromatic hydrocarbons (PAH).
Biochar Stability and Degradation
A clear, detailed, and accurate picture of the longevity and stability of biochar carbon in soils is essential. To predict the maximum extent of biochar degradation and stability, where monitoring will continue beyond the 4.5 year period of the Demonstrator for the field trials, the stability of the biochar will be tracked with time using various techniques including elemental analysis and high pressure hydrogen pyrolysis (HyPy).
How do we measure biochar persistence?
Hydropyrolysis (HyPy) determines the fraction of carbon of stable polyaromatic carbon (SPAC) of over 7 rings that will persist for at least 1,000 years with smaller ring aromatic structure potentially degradable. HyPy has gained significant traction for quantifying pyrolytic carbon in the environment in relation to other approaches (Meredith et al., Geochim Cosmochim Acta, 2012, 97, 131-147) of which biochar is a sub-set. HyPy is now included to quantify biochar persistence in Carbon Standards International, Global C sink methodology, v4; More Info). The method also enables the labile fraction comprising 1-7 ring aromatics and phenols (Rombola et al., J. Anal. Appl. Pyrol., 2016, 121-230) to be characterised by GC-MS, as a result of the much greater structural preservation compared to normal pyrolysis (Py-GC-MS).
As well as biochar, the high degree of reservation achieved for covalently-bound hydrocarbons mean that has found applications characterising hydrocarbon pollutants in the environment, such as oil spills, especially when these have been subjected to extensive degradation.
To arrange HyPy analysis, please contact: info@biochardemonstrator.ac.uk
