摘要
采用间歇法(batch method)模拟研究醋酸/醋酸铵缓冲体系中苹果酸对高岭石的溶解特征。结果表明,反应液中Al、Si浓度随苹果酸浓度提高、反应液pH降低及反应时间的推移而增加;有缓冲溶剂的苹果酸作用下,高岭石表现出Al的优先释放。且低浓度苹果酸(≤5mmol.L-1)时,随着酸度的升高,配体促进溶解速率(RL)减小;高浓度苹果酸(10mmol.L-1)时,随着酸度的升高,配体促进溶解速率(RL)增加,但增幅随pH的降低而减弱。随着酸度的升高,配体对高岭石溶解的相对作用减弱,但相对于质子对高岭石的溶解作用,本试验浓度及酸度范围内,其对高岭石溶解的贡献较小。
Experiment was conducted to investigate the dissolution character of kaolinite induced by malic acids with batch method in HAc/NH4Ac buffer solution. The results showed that the concen- tration of A1 and Si from kaolinite increased with concentration of malic acids and acidity of reactive solution and process of reactive time. The preferential Al-release of kaolinite was observed initially in HAc/NH4 Ae buffer solution of malic acids. Ligand-promoted kaolinite dissolution rates(R1.) reduced with the acidity enhancement when the concentration of malic acids was no more than 5 mmol ~ L-l; the rates(RL) were enhanced with the acidity enhancement when the concentration of malic acids wasn't less than 10 mmol ~ L 1 ,but the amplitude evidently weakened. The contribution amplitude of Ligand-promoted kaolinite dissolution evidently reduced with the acidity enhancement, but as far as the contribution of proton-promoted kaolinite dissolution was concerned, in the range of concentration and acidity of malic acids in the experimentation,the contribution of Ligand-promoted kaolinite dissolution was less
出处
《西北农业学报》
CSCD
北大核心
2013年第4期159-164,共6页
Acta Agriculturae Boreali-occidentalis Sinica
基金
国家自然科学基金(40371067)
中国科学院知识创新工程项目(KZCX3-SW-417
ISSASIP0208)
关键词
高岭石
苹果酸
配体
质子
Kaolinite
Malic acid
Ligand
Proton