Influence of Fe³⁺/Fe²⁺ Ratio on the Crystallization of Iron‐Rich Glasses Made with Industrial Wastes

Abstract

The influence of the Fe 3؉ /Fe 2؉ ratio on the crystallization of iron-rich glasses was investigated in this study. The glass batches were made from two hazardous industrial wastes: mud (goethite and jarosite) originating from the zinc hydrometallurgical process and electric arc furnace dust (EAFD). Glass compositions were prepared by adding different percentages of carbon powder. The crystallization process was investigated by a combined thermogravimetry/differential thermal analysis technique, in air or nitrogen atmospheres, using powder and bulk glass samples. The crystalline phases formed, i.e., pyroxene and spinels, and their relative ratio were determined by X-ray diffractometry. The experimental results indicated that melting temperature and crystallization behavior were influenced by the initial Fe 3؉ /Fe 2؉ ratio and by the amount of carbon added to the glass batch. For goethite and jarosite glass compositions, decreasing the Fe 3؉ /Fe 2؉ ratio increased the crystallization rate by favoring magnetite formation. For EAFD glass compositions, the addition of carbon to the batch inhibited chromite-magnetite spinel formation and favored the attainment of an amorphous glassy phase.

Sintered sanidine glass-ceramics from industrial wastes

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Glass-ceramics: Their production from wastes—A Review

“…The present review is concerned with reuse of waste materials to produce glass-ceramics. The versatility of the glass-ceramic production process is manifested by the many wastes that have been used as raw materials for glass-ceramics, which include coal fly ash [30][31][32][33], mud from zinc hydrometallurgy [34][35][36][37], slag from steel production [13,[38][39][40][41][42][43], ash and slag from waste incinerators [44][45][46][47][48][49][50][51][52][53][54][55][56][57], red mud from alumina production [58], waste glass from lamp and other glass products [59] as well as electric-arc furnace dust and foundry sands [60]. Much work has been carried out on the immobilisation of nuclear waste in glass and ceramic matrices and recently there has been some interest in the use of glass-ceramic matrices for this purpose [61,62].…”

Formation of a Nanocrystalline Layer on the Surface of Stone Wool Fibers

“…The dependence of bulk crystallization on the degree of oxidation has been reported elsewhere recently. [9][10][11][12][13][14][15] According to Cooper et al, 5 Yue et al, 6 and Burkhard, 7 the chemical process in a basaltic glass in atmospheric air at temperatures around T g is a diffusion process of network-modifying ions (primarily Ca 21 and Mg…”