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纤磷钙铝石类化合物系由自纤磷钙铝石CaAl3 (OH) 6(HPO4) (PO4)本身、经磷钙铝石CaAl3 (OH) 6(SO4) (PO4)到钾明矾石KAl3 (OH ) 6(SO4) 2 等的天然矿物族所组成的。它们表现出具有很大范围的阳离子置换系列 ,其中以Sr2 +和Ba2 +置换Ca2 +,REEs3 +置换Ca2 +和H+,As5 +置换P5 +,S6+/Se6+置换H+P5 +最为重要。随着置换的进行 ,其热动力学稳定性也逐渐增加。由此 ,纤磷钙铝石类化合物成为很能抗风化的矿物 ,在红土中尤其如此。厚的纤磷钙铝石层形成在闪长岩 (富Sr) ,碳酸盐岩 (富REEs)和含金石英脉 (富As)之上 ,从而保护整个磷酸盐红土 ,使之免受风化。以此方式 ,形成了桌状山脉或岛屿 ,他们具有未受覆盖的表面。这些“纤磷钙铝”石化合物为上述及其它元素形成一有效的地球化学障。“纤磷钙铝石”的这种天然地球化学固定作用可以用适当的母体或人工合成晶体来进行模拟 ,即通过金属阳离子交换或就地反应来模拟。这种固定作用还可用于处理天然和人造的放射性裂变产物、有毒的重金属元素、砷酸盐和硒酸盐、硫酸盐等。
The phyllosite-type compounds consist of CaAl3 (OH) 6 (HPO4) (PO4) itself, calcium aluminosite CaAl3 (OH) 6 (SO4) (PO4) to potassium alunite KAl3 OH) 6 (SO4) 2 and other natural mineral composition. They exhibit a wide range of cation exchange series, of which Ca2 + is replaced by Sr2 + and Ba2 +, Ca2 + and H + are replaced by REEs3 +, P5 + is replaced by As5 +, and H + P5 + is the most important substitution for S6 + / Se6 +. With the progress of substitution, its thermodynamic stability also gradually increases. As a result, the fiberglassite compound becomes a very weatherable mineral, especially in laterite. A thick layer of fiberlite is formed over the diorite (Sr rich), carbonate (REEs rich) and auriferous quartz veins (rich As) to protect the entire phosphate laterite from weathering . In this way, table-shaped mountains or islands are formed, with uncovered surfaces. These “phyllosilicate” stone compounds form an effective geochemical barrier to these and other elements. This natural geochemical affixation of “calicivsite” can be modeled with the appropriate precursor or synthetic crystals, either by metal cation exchange or in situ reaction. This fixing can also be used to treat natural and man-made radioactive fission products, toxic heavy metal elements, arsenate and selenate, sulfate and so on.