For every solute/adsorbent system tested, adsorption
equilibrium was attained in less than 2 h of contact. A
favourable adsorption of limonin to the neutral resins
tested was observed. Concerning naringin adsorption, a
good fit of both Freundlich and Langmuir models was
only observed when XAD-7 resin was used. Sigmoidprofiles were obtained for the adsorption of limonin to
granular activated carbon. Unfavourable isotherms were
also observed for limonin and naringin adsorption to ac-
tivated earths.
For every resin tested, unfavourable isotherm profiles
were obtained for the adsorption of carotenoids. A low
capacity for the adsorption of reducing sugars, vitamin C
and proteins was also observed for the adsorbents tested.
In addition, the estimated values for affinity and separa-
tion factors show a strong selective adsorption towards
limonin.
The results obtained are rather promising for industri-
al implementation of the selective removal of limonin
from orange juices by adsorption to the neutral resins
tested