Composition of leachate after the leaching step with 0.29 M H₂SO₄, S/L of 0.3 g mL⁻¹, 5 min leaching time at 25 °C.

Element	Fe	Al	Ti	Ca	Na	Mg	Mn	P	S	pH
Water + H 2 SO 4 (n = 4)
Concentration (mg L−1)	1358	196	3	1117	46	245	8	3270	4200	1.20
Standard deviation	±60	±15	±3	±46	±32	±12	±2	±302	±564	±0.12
Regenerated leachate + make-up water & H 2 SO 4 (n = 2)
Concentration (mg L−1)	1080	154	4	1299	848	240	8	3655	4303	1.26
Standard deviation	±123	±10	±4	±133	±13	±4	±5	±160	±580	±0.04