A NEW CONSECUTIVE DISSOLUTION METHOD FOR THE ANALYSIS OF SLAG CEMENTS

Until now, the best method of selective dissolution of ordinary portland cement (OPC) from ground granulated blast-furnace slag (BFS) has been a sodium-based alkaline aqueous solution of ethylenediamine-tetraacetate (ETDA) with chelating properties supplemented by the presence of 6 percent triethanolamine (TEA). Selectivity of the solvent is improved substantially, though, by replacing sodium with tetramethylammonium (TMA). The introduction of TMA slows the dissolution of BFS and accelerates the dissolution of OPC. In addition, the use of lithium as cation makes the EDTA-TEA solution a good solvent of BFS that permits separation from aggregates based on aluminosilicate rocks. Consecutive application of the two versions of the same chelating system thus allows good separation and quantitative dissolution of OPC and BFS from the unhydrated slag-cement. This paper examines the effect of the small lithium and the large TMA cation on the dissolution kinetics of OPC, BFS, and their hydration products in EDTA-solutions.

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  • English

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  • Accession Number: 00715293
  • Record Type: Publication
  • Files: TRIS
  • Created Date: Jan 1 1996 12:00AM