Kinetic modeling of metal ion transport for desorption of Pb(II) ion from oil palm fruit fibre (Elaeis guineensis) adsorbents

The kinetics of desorption of lead (II) ion from metal loaded adsorbent of mercaptoacetic acid modified and unmodified oil palm (Elaeis guineensis) fruit fiber was studied using different solutions, at different contact times. At the end of 25 minutes, 79.19%, 75.99%, 57.14%, 50.56% and 32.72% of Pb2+ were desorbed using 0.2 MHcl, 0.1 M H2S04, 0.1 MHNO3, 0.1 MNaOH and hot deionized H20 respectively for the 1.0 MOPF adsorbent. Desorption kinetic modeling of Pb2+ using the Elovich desorption and Pseudo-first Order Rate desorption equations showed that the latter described the kinetics of Pb2+ better. The desorption rate instant, β for 0.1 MHCl solution were: 7.27 x 10-1, 6.49 x 10-1 and 5.11 x 10-1, mg.g-1, .min-1, for UOPF, 0.5 MOPF and 1.0 MOPF adsorbents respectively. The surface residence time ح values for the 0.1 MHCl solutions were 24.83, 46.70 and 29.80 seconds for UOPF, 0.5 MOPF and 1.0 MOPF adsorbents respectively.