Pore development during CO₂ and H₂O activation associated with the catalytic role of inherent inorganics in sewage sludge char and its performance during the reforming of volatiles

We present a highly-detailed discussion on the pore development in sewage sludge char to better understand its transformation and subsequent role in volatiles reforming. Interactions with the pyrolytic gas can change the porosity of biochar that subsequently participates in the volatiles reforming, thus affecting the product yield and quality. The results demonstrated that H₂O activation was more susceptible to the catalytic effects of inorganics, pointing out the more selective nature of CO₂. Interestingly, we found important difference between ultra- and supermicropores role in the CO₂ activation and toluene conversion. Thus, we suggest distinguishing the micropore types in char porosity assessment.