3.8. Desorption studies
The adsorption studies have shown that for, 40.633 mg/L and
8.551 mg/L Ni(II) ions were adsorbed by 0.4g of MBAC and MBRC
respectively. Similarly, MBAC and MBRC adsorbed 28.98 mg/L and
5.98 mg/L Zn(II) ions, respectively. In desorption process, Ni(II) ion
was found to desorb 3.340 mg/L after 6 h and 3.369 mg/L after 24 h
from MBRC whereas 15.205 mg/L and 15.225 mg/L was desorbed
from MBAC after 6 h and 24 h, respectively. This means that only
39.96% 37.42% was desorbed from the adsorbents and 60.04% and
62.58% of Ni(II) was still adsorbed onto MBRC and MBAC, respectively.
Similarly, Zn(II) ion of 1.13 mg/L and 1.158 mg/L was desorbed after
6 h and 24 h, respectively from MBRC whereas 1.467 mg/L and
1.477 mg/L was desorbed from MBAC after 6 h and 24 h, respectively,
this indicated that 81.12% and 94.91% of Zn(II) are still left in MBRC
and MBAC. From this result, it can be seen that the adsorbents can be
used for a couple of cycles.