|
|
||||||||
Inst. of Agricultural Chemistry, Univ. of Naples, via Università 100, I-80055 Portici (Naples), Italy
* Corresponding author.
ABSTRACT
The aim of this work was to study: (i) the competitive adsorption of phosphate (P) and oxalate (OX) anions on an Al oxide as influenced by pH and order of anion addition; and (ii) the adsorption of P on and the desorption of OX from an Al precipitation product [Al(OH)x-OX] formed in the presence of OX ions. The amount of P adsorbed on Al oxide in the absence of OX decreased with increasing pH. In the absence of P, OX adsorption exhibited a broad maximum between pH 5.0 and 7.0, but rapidly decreased at a pH <5.0 or >7.0. The order of anion addition strongly influenced the adsorption of both P and OX. Maximum reduction in P adsorption occurred when OX was introduced before P, whereas reduction was negligible when P was added before OX. The efficiency of OX in reducing P adsorption was relatively high at acidic pH values, but it was poor at a pH >7.0. The presence of P strongly depressed OX adsorption when P was added before OX or when the anions were added together. The efficiency of P in reducing OX adsorption increased with increasing pH. Finally, the ability of P in replacing OX ions from Al(OH)x-OX was poor at pH values <7.0, but increased in alkaline environments with increasing pH. The data thus reveal that OX ions compete strongly with P for adsorption sites of Al oxides when they are added before the inorganic ions or are coprecipitated with Al in Al precipitation products, and mainly at acidic or neutral pH values.
Received for publication August 16, 1989.
This article has been cited by other articles:
![]() |
G. C. Murray and D. Hesterberg Iron and Phosphate Dissolution during Abiotic Reduction of Ferrihydrite-Boehmite Mixtures Soil Sci. Soc. Am. J., June 21, 2006; 70(4): 1318 - 1327. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. A. Jara, A. Violante, M. Pigna, and M. de la Luz Mora Mutual Interactions of Sulfate, Oxalate, Citrate, and Phosphate on Synthetic and Natural Allophanes Soil Sci. Soc. Am. J., February 2, 2006; 70(2): 337 - 346. [Abstract] [Full Text] [PDF] |
||||
![]() |
R. Giesler, T. Andersson, L. Lovgren, and P. Persson Phosphate Sorption in Aluminum- and Iron-Rich Humus Soils Soil Sci. Soc. Am. J., January 1, 2005; 69(1): 77 - 86. [Abstract] [Full Text] [PDF] |
||||
![]() |
K. J. Hutchison and D. Hesterberg Dissolution of Phosphate in a Phosphorus-Enriched Ultisol as Affected by Microbial Reduction J. Environ. Qual., September 1, 2004; 33(5): 1793 - 1802. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. C. Seaman, J.S. Arey, and P. M. Bertsch Immobilization of Nickel and Other Metals in Contaminated Sediments by Hydroxyapatite Addition J. Environ. Qual., March 1, 2001; 30(2): 460 - 469. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. De Cristofaro, J.Z. He, D.H. Zhou, and A. Violante Adsorption of Phosphate and Tartrate on Hydroxy-Aluminum-Oxalate Precipitates Soil Sci. Soc. Am. J., July 1, 2000; 64(4): 1347 - 1355. [Abstract] [Full Text] |
||||
![]() |
H. Wijnja and C.P. Schulthess Interaction of Carbonate and Organic Anions with Sulfate and Selenate Adsorption on an Aluminum Oxide Soil Sci. Soc. Am. J., May 1, 2000; 64(3): 898 - 908. [Abstract] [Full Text] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| The SCI Journals | Agronomy Journal | Crop Science | |||
| Vadose Zone Journal | Journal of Plant Registrations | ||||
| Journal of Natural Resources and Life Sciences Education |
Journal of Environmental Quality |
||||