## 4 Conclusions
**Informed Consent Statement:** Not applicable. **Data Availability Statement:** Not applicable. **Conflicts of Interest:** The authors declare no conflict of interest. \begin{table}
\begin{tabular}{c c c c} \hline \hline
**The Direction of a** & & & \\
**Gas Flow through the** & & & \\
**Catalyst Bed** & & & \\ \hline \multirow{6}{*}{axial} & \(\blacktriangledown\) & Simple design & \(\blacktriangledown\) & High gas flow resistances \\  & \(\blacktriangledown\) & Easy loading and unloading of the catalyst & \(\blacktriangledown\) & Increasing the volume of the catalyst bed \\  & \(\blacktriangledown\) & More efficient use of the available space & & requires increasing the reactor diameter—a \\  & & inside the reactor—the possibility of & & thicker and more expensive reactor shell \\  & & installing a larger volume of the catalyst bed & & undergoing faster exploitation \\ \hline \multirow{6}{*}{radial} & \(\blacktriangledown\) & & \(\blacktriangledown\) & More complex and expensive catalytic basket \\  & \(\blacktriangledown\) & Low gas flow resistances & & design \\  & \(\blacktriangledown\) & Low linear gas flow velocity through the catalyst bed & \(\blacktriangledown\) & The presence of a heavy top cover plate in \\  & \(\blacktriangledown\) & High efficiency of tail-gases purification from & \(\blacktriangledown\) & the upper part of the catalytic basket \\  & & nitrogen oxides & & \\  & \(\blacktriangledown\) & Possibility of using smaller catalyst shaped & & \\  & & bodies without the risk of excessive pressure & \(\blacktriangledown\) & More problematic loading and unloading of \\  & & drop increase & & the catalyst (including installing and \\  & \(\blacktriangledown\) & Possibility of varying the gas flow resistance & & uninstalling a top cover plate) \\  & & through the catalyst bed along the height of & \(\blacktriangledown\) & Problem with uniform gas distribution over \\  & & the catalytic basket (by using different holes & & the catalyst bed along the height of the \\  & & sizes and varying their location on the & & catalytic basket \\  & & perforated side walls of the basket) & \(\blacktriangledown\) & Settling of the catalyst bed—a risk of gas \\  & & bypassing & \\ \hline \multirow{6}{*}{lateral} & \(\blacktriangledown\) & Very low gas flow resistances & \(\blacktriangledown\) & Complex design, problematic in maintenance \\  & \(\blacktriangledown\) & Low linear gas flow velocity through the catalyst bed & & works \\  & & catalyst bed & \(\blacktriangledown\) & With the same volume of available space \\  & \(\blacktriangledown\) & The LFR reactor can be used in case of low & & inside the reactor compared to the axial and \\  & & gas flow rates—”end-of-pipe” location & & radial reactors, it is possible to install the \\  & \(\blacktriangledown\) & Very high efficiency of tail-gas purification & & smallest volume of the catalyst \\  & & from nitrogen oxides & \(\blacktriangledown\) & Problem with uniform gas distribution over \\  & \(\blacktriangledown\) & Possibility of using small catalyst shaped & & the catalyst bed, along the height of the \\  & & bodies & & cassettes \\  & & & \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Advantages and disadvantages of the catalytic basket design in deNO\({}_{\rm x}\)/deN\({}_{2}\)O reactors.