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研究了有机酸根离子与合成铝氧化物表面吸附磷解吸的相互关系。结果表明:（1）有有机酸时比无有机酸时吸附的磷具有更高的解吸率，无草酸且加磷pH为4时，0.01mol·L-1KCI对磷的解吸率最低，草酸与磷共存且pH为6时磷的解吸率最高;（2）高浓度有机酸可解吸低浓度有机酸难解吸的磷，草酸难解吸的磷可为等浓度的柠檬酸极解吸;（3）不同浓度草酸和柠檬酸对“铝-草酸”复合物吸附磷的解吸率比对Al（OH)x的低，而对“铝-柠檬酸”复合物吸附磷的解吸率则比对Al（OH）x的高;（4）柠檬酸对“铝-磷”复合物中磷的解吸量随柠檬酸浓度升高而增大。这些结果证明，有机酸对铝氧化物吸附磷的解吸机理包括配位交换和溶解，有机酸可促进磷的解吸，提高磷的有效性。
The relationship between organic acid ions and desorption of adsorbed phosphorus on the surface of aluminum oxide was studied. The results showed that: (1) When there was organic acid, the adsorbed phosphorus had higher desorption rate than that without organic acid, and no oxalic acid. When the pH was 4, 0.01mol·L-1 KCI had the lowest desorption rate of phosphorus, Phosphorus coexists and the pH is 6, the desorption rate of phosphorus is the highest. (2) High concentrations of organic acids can desorb the phosphorus that is desorbed by low concentrations of organic acids. The desorption of phosphorus by oxalic acid can be desorbed by the same concentration of citric acid. The desorption rate of phosphorus adsorbed on the aluminum-oxalate complex was lower than that of Al-oxalate complex at different concentrations of oxalic acid and citric acid, OH) x; (4) The desorption amount of phosphorus in “Al-P” complex by citric acid increased with the increase of citric acid concentration. These results demonstrate that the mechanism of desorption of phosphorus by organic acids on aluminum oxide includes coordination exchange and dissolution. Organic acids can promote the desorption of phosphorus and increase the availability of phosphorus.