摘要
已有资料表明原生和次生硅酸盐矿物、磷酸盐矿物等，可以去除污染水体和土壤中有机物质、重金属元素、 Ｒ Ｅ Ｅ、 Ｎ Ｈ＋４ 或某些细菌等，使环境得到良好修复。总结了目前非金属矿物用于环境修复的某些主要机理，即：①离子交换吸附机理：如对于蒙脱石矿物有（ Ｃｕ、 Ｐｂ、 Ｚｎ、 Ｈｇ、 Ｃｒ）（２～３）＋ ＋（ Ｃａ， Ｎａ）蒙脱石＝ （ Ｃｕ、 Ｐｂ、 Ｚｎ、 Ｈｇ、 Ｃｒ）蒙脱石＋ （ Ｃａ２＋ 、 Ｎａ＋ ）；②配合作用机理：如 Ｃｒ３＋ 可进入蒙脱石矿物层间，在层间可与（ Ｓｉ Ｏ４）４－ 中的氧发生配合作用；③改性作用机理：将蒙脱石粘土加入短链季胺盐形成有机粘土矿物，大大增加了蒙脱石吸附有机化合物的能力；④共沉淀作用机理：如碳酸盐矿物在不同的 ｐ Ｈ 下可形成不同的碳酸根离子，它们可与某些重金属离子形成沉淀；⑤催化氧化作用机理：对于难去除的有机化合物可以加入某些催化氧化剂，如 Ｈ２ Ｏ２ 等，使矿物表面更具氧化性，以达到去除如酚、醛、多氯联苯等有机物的目的。非金属矿物在修复环境中不仅是单一的机理，而是几种机理的结合作用。虽然这里总结出 ５ 种机理。
The data and information have showed that nometalic minerals including primary and secondary silicates and apatites can absorb heavy elements, REE, organic materials, and some bacteria. These minerals can remedy environment efficially, which have been polluted both in waters and in soils. This article showed the mechanisms as follow: (1)Experiments have showed that when some heavy elements are high in environment, after adding bentonites heavy metal elements can exchange Ca 2+ and Na + from bentonites, according to the lowest energy law and matter conversation principle. A typical mechanism is like (Cu, Pb, Cd, Hg, Cr) (2~3)+ +(Ca 2+ , Na +) bentonite=(Ca 2+ ,Na +)+(Cu, Pb, Zn, Cd, Hg, Cr) bentonite. So heavy metal elements are removed from environments. (2)Besides absorbing on the surface, some elements such as Cr 3+ can enter layers of bentonites and complex with oxygen of silicate radics there, which have been confirmed by different parameters. (3)To remove much more environmental organic components TMA + and TMPA + are often added into bentonite and organic clay minerals are formed. These types of clays can remove aroma and adipose efficiently. The rate of removing organic matter depends on the mineral structures. (4)Apatites can release different carbonate ions in different pH. These ions combine with Pb, Cu, Zn, Cd and pricipitate from the solutions, especialy in mining and metallurgy districts.(5)When H 2O 2 contacts with surfaces of nometalic minerals, the free radicals (OH·) produce, in the catalysis of Fe 2+ or Fe 2O 3. The surfaces after oxidizing by OH· oxidized phneols, aldehydes,and polychlorinebenzene easier. So rigid elements are removed. Although the five mechanisms are proposed here, some are to be further studied now. In environments when polluted elements are removed, several mechanisms are acted at the same time.
出处
《地球科学进展》
CAS
CSCD
1999年第5期475-481,共7页
Advances in Earth Science
