天然药用矿物蒙脱石除铅实验的微波应用

LABORATORY REMOVAL OF Pb FROM NATURAL MEDICINE MINERAL MONTMORILLONITE BY MICROWAVE IRRADIATION

蒙脱石是一种药用矿物。天然产出的蒙脱石中常含有对人体有害的Pb等重金属元素。为了除去这些重金属元素,我们分别对蒙脱石进行了酸溶处理和EDTA萃取实验,在实验过程中分别采用了常规加热和微波加热。结果表明酸溶法只能除去65%左右的Pb,而在以下条件下Pb的去除率可达93.75%:0.05 mol/L的Na-EDTA溶液;固液比1∶5;中档微波处理10 min。在该条件下经过处理的蒙脱石Pb含量小于5×10-6,符合药用标准。

Montmorillonite （MMT） is a mineral that can be used for medical purpose. Naturally occurred MMT usually contains heavy metal elements such as Pb, whie are harmful to human health. In order to remove the heavy metal, MMT was treated with nitric acid and EDTA solution respectively, and enhanced by conventional heating or micro- wave radiation. It is found that in nitric solution the removal ratio of Pb from MMT is only about 65 %, while in the following conditions, the removal ratio of Pb can be as high as 93.75% ： in 0.05 mol/L Na-EDTA solution, with the solid/liquid ratio of 1 ： 5, treated with moderately intense microwave radiation for 10 minutes. Under these conditions, the contents of Pb in the treated montmorillonite are below 5 ppm, fitting with the requirement for medical use.