Mg^(2+)对膨润土载体缓释肥缓释效果的影响  

Study on the action of magnesium ion in slow-release fertilizer with carrier of bentonite

作　　者：徐俊虎[1] 王雁晖[1] 苏红玉[1] 卢静[1] 庞炳颖 

机构地区：[1]中国城市建设研究院,北京100120

出　　处：《再生资源与循环经济》2016年第5期36-40,共5页Recyclable Resources and Circular Economy

摘　　要：采用天然多孔的矿物膨润土作为磷酸二氢铵肥的载体,并将其与脲醛树脂和镁盐按一定的比例添加混合、压片固化制成膨润土载体缓释氮磷复合肥。通过水中溶出率法和沙柱淋溶法综合考察了镁盐类型及镁盐用量对缓释肥料养分释放性能的影响,发现其缓释性能随镁盐添加量的增大而增加,5%的MgCl_2和15%的MgCO_3作为缓释肥的添加成分效果最优,但当MgCl_2,MgCO_3两种镁盐用量进一步增加后缓释效果不显著。研究表明载体肥料在添加镁盐后,Mg^(2+)在蒙脱石以及磷酸盐之间形成了磷酸镁铵化合物,即鸟粪石,提升了肥料的缓释效果。As the carrier of ammonium dihydrogen phosphate fertilizer, natural porous mineral bentonite was mixed with some urea-formaldehyde resin and magnesium salt according to a certain ration. With the help of electric pressure machine, the slow release fertilizer was well made. Through the method of water dissolution rate and the sand column leaching solution, the research had found that the dosage of magnesium carbonate is more, the effect of the nutrient release of the prepared slow release fertilizer tablets is better. And the slow-release effect of sustained release tablets was best, when the dosage of magnesium chloride and magnesium carbonate were 5% and 15%. Slow-release effect is not significant when the dosage of magnesium salt increase more. As magnesium chloride is soluble salts and its solubility in water is big, it will release a small amount of magnesium ion, reaction with ammonium ion and phosphate of the matrix of the slow release fertilizer to form a small amount of struvite, which have enhanced the slow-release effect.

关 键 词：Mg2+ 膨润土 缓释肥 缓释机理 

分 类 号：S145.6[农业科学—肥料学]