Bhuiyan Iftekhar U, Mouzon Johanne, Schröppel Birgit, Kaech Andres, Dobryden Illia, Forsmo Seija P E, Hedlund Jonas
Chemical Technology, Luleå University of Technology, SE-971 87 Luleå, Sweden.
Natural and Medical Sciences Institute (NMI), University of Tübingen, 72 770 Reutlingen, Germany.
Microsc Microanal. 2014 Feb;20(1):33-41. doi: 10.1017/S1431927613013950. Epub 2014 Jan 7.
Sodium-activated calcium bentonite is used as a binder in iron ore pellets and is known to increase strength of both wet and dry iron ore green pellets. In this article, the microstructure of bentonite in magnetite pellets is revealed for the first time using scanning electron microscopy. The microstructure of bentonite in wet and dry iron ore pellets, as well as in distilled water, was imaged by various imaging techniques (e.g., imaging at low voltage with monochromatic and decelerated beam or low loss backscattered electrons) and cryogenic methods (i.e., high pressure freezing and plunge freezing in liquid ethane). In wet iron ore green pellets, clay tactoids (stacks of parallel primary clay platelets) were very well dispersed and formed a voluminous network occupying the space available between mineral particles. When the pellet was dried, bentonite was drawn to the contact points between the particles and formed solid bridges, which impart strength to the solid compact.
钠活化钙膨润土用作铁矿石球团的粘结剂，已知其可提高湿态和干态铁矿石生球团的强度。在本文中，首次使用扫描电子显微镜揭示了磁铁矿球团中膨润土的微观结构。通过各种成像技术（例如，用单色和减速电子束在低电压下成像或低损失背散射电子成像）和低温方法（即高压冷冻和在液态乙烷中骤冷冷冻）对湿态和干态铁矿石球团以及蒸馏水中的膨润土微观结构进行了成像。在湿态铁矿石生球团中，粘土类质同象体（平行的原生粘土片层堆叠）分散得非常好，并形成了一个占据矿物颗粒间可用空间的庞大网络。当球团干燥时，膨润土被吸引到颗粒之间的接触点并形成固体桥，从而赋予固体压块强度。
