Fig. 2 shows that P removal was greatly affected by the initial pH values in aqueous solutions. With the initial pH was increased from 2.48 to 3.57 the P removal efficiency was increased from 82.3% to 98.0% and the final pH was increased from 3.03 to 4.52; as the initial pH was in the range of 3.57–12.1 the P removal efficiency were nearly steady at 98% and the final pH was gradually increased from 4.52 to 6.27; the P removal efficiency was decreased and the final pH was increased steeply as the initial pH was over 12.1. Pyrrhotite reduced P concentrations in the wastewater to a very low level (around 0.3 mg/L) as the initial pH values of wastewater were between 3.57 and 12.1. The wide pH range shows that pyrrhotite can be highly used to almost all types of wastewater for P removal.