Sulfur infiltration system

Figure 2. Sulfur infiltration system used in this investigation...

Analyses of Immersion Liquids and Precipitates. The experiment under nitrogen provided vital information on the stability of the concrete-water system and the reactions taking place. Under a normal atmosphere, sulfur leached from the infiltrated concrete was deposited on the surface as described or was precipitated as a fine mud in the immersion water, together with minor gypsum and calcite. Under nitrogen, however, the liquid turned yellow to pale orange, its pH rose to 11 or more, and precipitation ceased. When the solution was exposed to air, it turned colorless and precipitated sulfur rapidly. This was accompanied by a pH drop to a normal 7.3 level. 

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