Analysis of Active Ion-Leaching Behavior and the Reaction Mechanism During Alkali Activation of Low-Calcium Fly Ash

International Journal of Concrete Structures and Materials

Table 2 Percent increases in the leaching of Si⁴⁺, Al³⁺ and Ca²⁺.

Active ions	Time (h)	0.25 mol L⁻¹	0.75 mol L⁻¹	1.25 mol L⁻¹	2 mol L⁻¹
Si⁴⁺	3	4.21	7.37	12.42	13.68
	6	8.33	12.50	22.08	29.17
	12	12.50	16.67	29.17	37.50
	24	19.79	26.04	45.63	58.33
	48	23.96	35.42	64.58	89.06
	72	26.04	39.58	76.04	107.29
Al³⁺	3	26.67	48.33	95.00	106.67
	6	50.00	84.76	139.52	170.48
	12	64.89	91.11	184.44	215.56
	24	85.22	117.39	202.61	252.17
	48	111.30	164.35	241.74	310.87
	72	120.87	170.43	258.26	334.78
Ca²⁺	3	− 94.9	− 94.9	− 94.9	− 94.9
	6	− 94.4	− 95.6	− 96.3	− 95.0
	12	− 94.5	− 95.1	− 95.1	− 95.1
	24	− 92.4	− 92.9	− 92.9	− 92.4
	48	− 91.8	− 93.0	− 93.6	− 92.4
	72	− 92.4	− 92.9	− 92.9	− 93.5