Slags acid/base properties

J.A. Duffy, M.D. Ingram and I.D. Sommerville, Acid Base Properties of Molten Oxides and Metallurgical Slags, J. Chem. Soc. Faraday Trans. 74 (1978) 1410-1419. 

Rock wool fibers can be characterized by their acidity modulus, Mj, which describes the ratio of acidic to basic oxides. If Ms< 1.2, the fiber is called slag wool, the base material of which is cinder. Nowadays, such low quality fibers are not produced any more because they are very brittle and show a poor chemical resistance. If Mj= 1.2-1.5, the fiber is considered to be a mineral wool, the base materials of which are basic volcanic rock and cinder. These fibers are brittle, but have acceptable insulation properties, hence their significance in the construction industry is high. If Ms> 1.5, the fiber is called rock wool, and if its base material is basalt then it is named basalt wool (basalt fiber, BF). The base of basalt fiber is basalt, which is a volcanic, over-ground, effusive rock saturated with 45-52 wt.% Si02. Due to the circumstances of its formation, basalt has several excellent properties. In addition to its high elasticity modulus and excellent heat resistance. 

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