Li Chunjuan, Ma Jun, Shen Jimin, Wang Peng
School of Municipal and Environmental Engineering, Harbin Institute of Technology, 202 Haihe Road, Harbin 150090, Heilongjiang, People's Republic of China.
J Hazard Mater. 2009 Jul 30;166(2-3):891-6. doi: 10.1016/j.jhazmat.2008.11.111. Epub 2008 Dec 6.
Removal of phosphate in secondary effluents was investigated in presence of Fe(2+)/H(2)O(2). The effect of H(2)O(2)-dose, Fe-dose and initial phosphate concentration were assessed. The results indicated that Fe(2+)/H(2)O(2) could greatly increase the removal of phosphate compared with those achieved by Fe(2+) alone. For initial phosphate concentration of 0.97-3.75 mg P/L, phosphate removal rates of 50-60% were observed at 1:1 molar addition of Fe(II). However, a 125% excess of Fe-dose was necessary for complete phosphate removal. The experimental data demonstrated that removal of phosphate with Fe(2+)/H(2)O(2) was higher than that observed with ferric coagulation alone. This fact suggested that in situ formed Fe(III) having much affinity for ligand phosphate. Chemical co-precipitation was considered as the dominant mechanism about phosphate removal in presence of Fe(2+)/H(2)O(2). The electron paramagnetic resonance (EPR) spectra tests in secondary effluents showed that Fe(2+)/H(2)O(2) could produce an increasing hydroxyl radical concentration with a decrease in both H(2)O(2) dosage and phosphate concentration. Fe(2+)/H(2)O(2) had the potential to be utilized for removal of phosphate due to the lower cost and the higher phosphate removal capability.
研究了在Fe(2+)/H(2)O(2)存在的情况下二级出水磷酸盐的去除情况。评估了H(2)O(2)剂量、Fe剂量和初始磷酸盐浓度的影响。结果表明，与单独使用Fe(2+)相比，Fe(2+)/H(2)O(2)能大大提高磷酸盐的去除率。对于初始磷酸盐浓度为0.97 - 3.75 mg P/L的情况，在Fe(II)摩尔添加比为1:1时，观察到磷酸盐去除率为50 - 60%。然而，要完全去除磷酸盐，Fe剂量需要过量125%。实验数据表明，Fe(2+)/H(2)O(2)去除磷酸盐的效果高于单独的铁混凝法。这一事实表明原位形成的Fe(III)对配体磷酸盐具有很大的亲和力。化学共沉淀被认为是在Fe(2+)/H(2)O(2)存在下磷酸盐去除的主要机制。二级出水的电子顺磁共振(EPR)光谱测试表明，Fe(2+)/H(2)O(2)随着H(2)O(2)剂量和磷酸盐浓度的降低，能产生不断增加的羟基自由基浓度。由于成本较低且磷酸盐去除能力较高，Fe(2+)/H(2)O(2)有潜力用于去除磷酸盐。
