# Fine Activated Carbon from Rubber Fruit Shell Prepared by Using ZnCl\({}_{2}\) and KOH Activation
## 3 Results
### Characterization of RFSFACs
\begin{table}
\begin{tabular}{c c c c c c c c c} \hline  & \multirow{2}{*}{\begin{tabular}{c} **BET** \\ **(m\({}^{2}\)/g)** \\ \end{tabular} } & \multirow{2}{*}{\
\begin{tabular}{c} **Adsorption** \\ **Quantity** \\ **(cm\({}^{3}\)/g)** \\ \end{tabular} } & \multirow{2}{*}{
\begin{tabular}{c} **Average Pore** \\ **Diameter (nm)** \\ \end{tabular} } & \multicolumn{6}{c}{**Pore Area**} \\ \cline{5-10}  & & & & **(m\({}^{2}\)/g)** & & **Mesopores** & **Micropores** & **Macropores** \\ \cline{5-10}  & & & & **(m\({}^{2}\)/g)** & **(\%)** & **(m\({}^{2}\)/g)** & **(\%)** & **(m\({}^{2}\)/g)** & **(\%)** \\ \hline RFSAC & 178 & 55.91 & 4.83 & 11.41 & 68 & 5.18 & 31 & 0.24 & 1 \\ RFSAC1 & 42 & 27.35 & 9.03 & 9.25 & 78 & 2.19 & 18 & 0.44 & 4 \\ RFSAC2 & 141 & 58.03 & 5.21 & 16.38 & 66 & 8.08 & 32 & 0.46 & 2 \\ RFSAC3 & 160 & 61.83 & 4.64 & 16.39 & 63 & 9.34 & 36 & 0.44 & 2 \\ RFSAC4 & 256 & 87.20 & 4.19 & 13.88 & 68 & 6.39 & 31 & 0.20 & 1 \\ RFSAC5 & 400 & 132.92 & 3.54 & 24.74 & 68 & 11.50 & 32 & 0.20 & 1 \\ RFSAC6 & 456 & 150.38 & 3.44 & 28.46 & 70.1 & 11.95 & 29.4 & 0.20 & 0.5 \\ \hline \end{tabular}
\end{table} 
Table 3: Textural properties of RFSACs. Figure 5 presents the nitrogen adsorption isotherms of the various RFSFACs. For all of the products, the nitrogen adsorption capacity increases rapidly in the low relative pressure regime (0 < P/P0 < 0.2), but then increases more slowly with an increasing relative pressure before reaching an approximately constant value at a relative pressure of around P/P0 = 0.98. The isotherms are consistent with those reported in [48; 51; 52; 53] and can be classified as type I isotherms based on the IUPAC classification. For both activation agents, the nitrogen adsorption quantity increases with an increasing impregnation ratio due to a widening of the microporosity. Since all of the RFSFACs have a similar isotherm type, it can be inferred that they all contain micropores. However, for a given relative pressure and impregnation ratio, the ZnCl2-activated products yield higher nitrogen adsorption than the KOH-activated samples. This may be due to the pore area and mesoporous structures that were created by ZnCl2 which were higher than KOH. Thus, among all of the present RFSFAC products, the product prepared using the ZnCl2 activating agent with an impregnation ratio of 1:5 yields the highest nitrogen adsorption quantity of 150.38 cm3/g. Figure 6 presents SEM micrographs of the various RFSFACs. Large pores or macropores are evident in all of the samples. However, no mesoporous or micropores can be seen  
Figure 4: (**a**) Barrett-Joyner–Halenda (BJH) adsorption pore area distribution; (**b**) pore size distribution for RFSFACs, prepared with different activating agents and impregnation ratios. Figure 5: Nitrogen desorption isotherms for RFSFACs prepared with different activating agents and impregnation ratios. due to the relatively low magnification level of the images (5000\(\times\)). Overall, the images show that for both activating agents, the percentage of macropores remains approximately unchanged as the impregnation ratio increases (see also Figure 4b and Table 3).