Thermodynamic analysis of alkaline mineral dissolution in alkali solution

The dissolution reactions of alkaline minerals in alkali solution were studied by the thermodynamic method, and the capacities of alkali released from alkaline minerals and their effect on alkali-silica reactions (ASR) were analyzed also. The results indicate that the sequence of capacity in alkali released from alkaline minerals is dawsonite > leucite > nepheline > dehydration analcime > paragonite > muscovite > jadeite > Na-feldspar > K-feldspar in alkali solution with a pH value higher than 13. With the increase of OH^- concentration in alkali solution, the dissolution degree of the common minerals in aggregates such as Na-feldspar and K-feldspar are increased remarkably, but the dissolution degree of dawsonite and nepheline are decreased slightly. Furthermore, it is pointed out that decreasing the pH value of the pore solution and preventing water from entering into the pore solution may be suitable way to restrain alkali from being released from the aggregate. The theoretical principle is introduced for inhibiting ASR according to the thermodynamic analysis.