Kinetic and Thermodynamic Aspects of the Adsorption of Pb2+ and Cd2+ Ions on Tripolyphosphate-Modified Kaolinite Clay.
| dc.contributor.author | Unuabonah, Emmanuel | |
| dc.date.accessioned | 2022-05-06T13:10:19Z | |
| dc.date.available | 2022-05-06T13:10:19Z | |
| dc.date.issued | 2007 | |
| dc.description.abstract | Kaolinite clay obtained from Ubulu-Ukwu, Delta state in Nigeria was modified with tripolyphosphate reagent to obtain TPP-modified Kaolinite clay. The kinetics and thermodynamics of the adsorption of Pb2+ and Cd2+ by TPP-Kaolinite clay were studied. Increasing temperature and initial metal ion concentration increased the sorption capacity of the adsorbent. The rates of adsorption of both Pb2+ and Cd2+ increased with increasing temperature but decreased with increasing initial metal ion concentration and time. The pseudo-second-order initial sorption rates for the sorption of Pb2+ were found to be higher than those of Cd2+. Pseudo-first-order model was found to only describe well, the data obtained in the first 8 min of the adsorption process. The sorption of both metal ions was endothermic and spontaneous with H◦ values of +13.94 kJ mol−1 and +24.93 kJ mol−1 for Pb2+ and Cd2+, respectively. Activation energy values obtained were between +8 kJ mol−1 and +22 kJ mol−1. These values suggest that the rate-controlling step in the adsorption of Pb2+ and Cd2+ by TPP-Kaolinite clay was diffusion-controlled. The sorption of metal ions from binary solutions of both metal ions at different initial metal ion concentrations reduced the initial sorption rates of the adsorption of Pb2+ by TPP-Kaolinite clay and increased that for Cd2+. The adsorption capacity of TPP-Kaolinite clay for both metal ions was also decreased by simultaneous presence of both metal ions. | en_US |
| dc.identifier.uri | http://dspace.run.edu.ng:8080/jspui/handle/123456789/2785 | |
| dc.publisher | Elsevier: Chemical Engineering Journal | en_US |
| dc.subject | Kaolinite clay | en_US |
| dc.subject | Adsorption of metals | en_US |
| dc.subject | Endothermic | en_US |
| dc.subject | Tripolyphosphate | en_US |
| dc.title | Kinetic and Thermodynamic Aspects of the Adsorption of Pb2+ and Cd2+ Ions on Tripolyphosphate-Modified Kaolinite Clay. | en_US |
| dc.type | Article | en_US |