The research programme of GreenCarbon consisted of four strongly interconnected work packages (WPs 4-7):
WP 4: Pyrolysis Conversion Routes for Dry Feedstocks. With the aim to set the most appropriate slow pyrolysis process conditions, several experimental studies have already been conducted. Regarding the continuous intermediate pyrolysis, experimental studies were also done in order to establish the most appropriate characteristics of such systems at laboratory scale. Finally, a comprehensive and beyond the-current-state-of-knowledge pyrolysis/carbonisation single-particle model has already been developed.
WP 5: HTC Conversion Routes for Wet Feedstocks. The objective of this WP was the assessment of the potential of different wet biomass sources (including lignin from bio-refinery processes) to produce engineered hydrochars or pyrochars through an HTC process or a cascaded HTC-fast pyrolysis process, respectively. A high number of experiments was already conducted at both laboratory and pilot-plant scale in order to set the most appropriate operating conditions in terms of energy efficiency as well as the properties of the produced hydrochars.
WP 6: Refining of BCs and Advanced Applications. This WP was designed for the functionalisation and modification of the biomass-derived carbons (BCs) produced within the previous WPs. Activated carbons (ACs) from corresponding BCs were developed for both CO2 capture and biogas desulphurisation purposes through several synthesis methods (based on hydrothermal treatment + soft templating, and hard templating + chemical vapour deposition). Several pyrochars have been physically and chemically activated to be used as low-cost and sustainable catalysts for cracking and reforming of pyrolysis vapours. Furthermore, metal-based catalysts supported onto activated carbons have been synthetised to evaluate their performance in catalytic upgrading and CO2 methanation in terms of temperature required, conversion, and selectivity towards H2 and CH4, respectively.
WP 7: Sequential Biochar Systems. The objective of this WP was to integrate expertise across the GreenCarbon network, focusing on identifying synergistic sequences for BC uses, spanning engineering, agricultural and horticultural applications, in order to maximise the added-value and minimise carbon footprint across the whole chain. Several experimental studies have been conducted to assess: (a) the effect of biomass feedstock and pyrolysis conditions on the carbon sequestration potential of BCs, and (b) the effect of replacing peat by BCs as growing media. In addition, several uses of biochar as adsorbent and regeneration pathways of spent biochars have been studied in detail in order to propose sequential uses of biochar.
25 scientific papers emanating from GreenCarbon has been published so far in JCR-indexed journals (Q1 and Q2 quartiles in their respective categories). I should be noted that several additional articles are now under progress at different stages (writing; submission, and revision). In any case, the objective initially pursued (at least 20 articles published at the end of the project ) has been reached.
Most of the identified exploitable results are still on a low technology readiness level (TRL), since they represent advanced materials or sophisticated mathematical models. However, all the nodes within the network will continue sharing the Foreground related to these results beyond GreenCarbon. Despite the fact that they are not able to be commercialised in the short-term, further synergistic development (between partners from both within and outside the network) will be able to increase TRL up to the more practical levels.
