含钾矿物中钾的释放及其与溶液环境中离子种类的关系

通过室内试验研究探讨5种含K矿物中K在不同溶液中的释放规律(释放量和释放速率).结果表明,不同含K矿物中K释放速率和释放量的顺序均表现为:黑云母>蛭石>金云母≥白云母>钾长石,不同K矿物释K速率在酸溶液中差异最大,其次在钙和钠盐溶液中,在水中的速率差异最小,这主要是受其矿物本身结构的影响.不同离子对含K矿物中非交换态K释放的促进作用差异显著:H~+>>Ca~(3+)>Na~+>H_2O>NH_4~+.随矿物K有效性增加,H~+和Ca~(2+)对矿物K释放的促进作用越大,而且H~+较Ca~(2+)对黑云母、金云母和长石中的K有更突出的促释作用.此外,Ca~(2+)较Na~+显著促进了黑云母和蛭石中K的释放,但对其他矿物中K释放的影响两者无显著差异.NH~+_4则显著抑制了各种矿物中K的释放,对黑云母和蛭石的抑制作用更强于对金云母和白云母的作用.

Dynamic release of potassium from potassium bearing minerals as affected by ion species in solution

The release disciplinarians, including cumulative K-release and release rate of potassium from five potassium bearing minerals under various solutions were studied. Results showed that the release rates of K from five K-bearing minerals under different solutions follow the order of biotite > vermiculite > phlogopite > muscovite > feldspar. The diversity between the release rates of K from different minerals under the acid solution was significant, follow by the calcium and sodium solutions, the distill water reversed; it depended on the structure of the minerals. Different ions had different abilities to promote the release of non-exchangeable K from different minerals: H~+>> Ca~(2+)> Na~+> H_2O > NH_4~+. With the increase of the availability of mineral K, H~+ and Ca~(2+) had greater effect on mineral potassium release. Furthermore, the effects of H~+ and Ca~(2+) on biotite, phlogopite, and feldspar were distinct. To vermiculite and biotite, Ca~(2+) accelerated the release of potassium distinctly rather than Na~+. However there was no difference between Ca~(2+) and Na~+ when they extracted other three types of mineral. However, NH_4~+ restrained potassium release from every kind of minerals remarkably, comparing to phlogopite and muscovite, the cffccts of restrain on vermiculite and biotite were stronger.