# Biomass-Based Chemical Looping Gasification: Overview and Recent Developments
## 3 Looping Materials in Chemical Looping Gasification of Biomass
### Performance of Looping Materials
\begin{table}
\begin{tabular}{c c c c} \hline \hline
**Type of OC** & **Operating Temp.** [\({}^{\circ}\)C] & **Support Materials** & **Advantage** & **Disadvantage** \\ \hline Ni-based & 900–1100 & \begin{tabular}{c} Al\({}_{2}\)O\({}_{3}\), MgAl\({}_{2}\)O\({}_{3}\), ZrO\({}_{2}\), \\ Bentonite, TiO\({}_{2}\), MgO \\ SiO\({}_{2}\) \\ \end{tabular} & \begin{tabular}{c} Very high reactivity and selectivity, \\ strong catalytic properties for \\ hydrocarbon conversion, high \\ oxygen transport capacity, high \\ stability, low agglomeration \\ \end{tabular} & \begin{tabular}{c} Sulfur deactivation, \\ high cost, health, and \\ safety issues \\ \end{tabular} \\ \hline Fe-based & \begin{tabular}{c} Al\({}_{2}\)O\({}_{3}\), MgAl\({}_{2}\)O\({}_{4}\), TiO\({}_{2}\), \\ SiO\({}_{2}\), YSZ, CeO\({}_{2}\), ZrO\({}_{2}\) \\ \end{tabular} & \begin{tabular}{c} Environmentally friendly and \\ non-toxicity, low cost, high \\ mechanical strength, high \\ chemical stability \\ \end{tabular} & \begin{tabular}{c} Relatively low \\ reactivity, low oxygen \\ transport capacity, \\ agglomeration issue, \\ low solid circulation \\ rate \\ \end{tabular} \\ \hline Cu-based & \begin{tabular}{c} \(<\)800 \\ \end{tabular} & \begin{tabular}{c} Al\({}_{2}\)O\({}_{3}\), CuAl\({}_{2}\)O\({}_{4}\), TiO\({}_{2}\), \\ SiO\({}_{2}\), CeO\({}_{2}\), ZrO\({}_{2}\), \\ Bentonite, MgO, \\ MgAl\({}_{2}\)O\({}_{4}\) \\ \end{tabular} & \begin{tabular}{c} High reactivity and oxygen \\ transport capacity, low cost and \\ toxicity, high chemical and \\ mechanical stability, \\ environmentally friendly. No \\ demand for external heat \\ \end{tabular} & \begin{tabular}{c} Agglomeration and \\ de-fluidization due to \\ the low melting point \\ of Cu \\ \end{tabular} \\ \hline Mn-based & \begin{tabular}{c} Al\({}_{2}\)O\({}_{3}\), MgAl\({}_{2}\)O\({}_{4}\), TiO\({}_{2}\), \\ SiO\({}_{2}\), ZrO\({}_{2}\), bentonite \\ \end{tabular} & \begin{tabular}{c} Low cost and non-toxicity, \\ environmentally friendly \\ \end{tabular} & \begin{tabular}{c} Sulfur deactivation, \\ relatively low oxygen \\ transport capacity, \\ agglomeration, low \\ reactivity with fuels \\ \end{tabular} \\ \hline Co-based & \
\begin{tabular}{c} YSZ, Al\({}_{2}\)O\({}_{3}\), CoAl\({}_{2}\)O\({}_{4}\), \\ TiO\({}_{2}\), SiO\({}_{2}\), ZrO\({}_{2}\), \\ bentonite \\ \end{tabular} &
\begin{tabular}{c} High cost and \\ environmental impact \\ and health issue, low \\ reactivity with fuels \\ \end{tabular} \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Overview of common types of oxygen carriers in chemical looping processes [9; 11; 12; 14; 18]. carrier converted more than 75% [9; 100]. Additionally, gas sulfur compounds in the syngas possibly react with oxygen carriers and produce various sulfur compounds that may cause the deactivation of looping materials. During thermochemical conversion processes, the inorganic matters in biomass are converted into the solid residual produced that can cause several problems for the performance of oxygen carriers and the system. Biomass ash composition is a complex mixture of inorganic-organic matters with solid, liquid, and gaseous phases from various origins. In the solid phase, ash is composed of inert materials from feedstock and un-reacted matters. In chemical looping processes, the interaction between biomass ash and oxygen carrier could be a significant issue. [PERSON] et al. [101] reported that the performance of iron ore oxygen carrier was significantly influenced by the biomass ash type, resulting in serious particle sintering and subsequent deactivation of oxygen carrier with SiO\({}_{2}\)-rich ash, whereas K-rich ash with lower SiO\({}_{2}\) content could efficiently improve the performance of oxygen carrier during cycle experiments.