Effect of Tire-Char Ash on the Extent of Synergy during CO₂ Cogasification with Hydrochar from Potassium-Rich Coconut Fiber

Abstract

The influence of inherent tire char ash during co-gasification with coconut hydrochar prepared at different intensities was investigated by thermogravimetric analysis to ascertain the extent to which synergistic interaction, reactivity, and activation energy reduction were altered. High-ash tire tread (TT) and low-ash sidewall (SW) both exhibited enhanced synergy, reactivity, and activation reduction upon cogasification with hydrochars; however, the extent of promotion was more pronounced in SW-hydrochar blends. This difference was caused by the inhibiting nature of TT inherent ash, particularly the role of Sicontaining compounds. Inhibition in TT-hydrochar blends was mainly due to the promotion of alkaline and alkaline earth metal transformation into inactive silicates, and to a lesser extent, the mass transfer effect caused by accumulated ash, especially at conversions higher than 70%. The extent of enhancement correlated well with the concentration of available alkaline and alkaline earth metals. The findings may be useful in justifying the exclusion of high ash tire char as gasification feedstock to mitigate ash-related problems.

The effects of two different biochars on the characteristics of saline acid sulfate soil

“…Especially, the concentration of exchangeable K in the CB‐added soil greatly increased compared with the no‐biochar‐added soil, which could be explained by the high concentration of the element in CB. CB was found to have a great concentration of potassium (Hungwe et al, 2020, 2021), which was also reflected through a great concentration of exchangeable K in the coconut biochar (Table 1). These findings indicate that the initial properties of feedstocks and their consequent biochars are important in determining the properties of the biochar‐added soil.…”