Ozacar Mahmut, Sengil I Ayhan
Department of Chemistry, Science & Arts Faculty, Sakarya University, 54100 Sakarya, Turkey.
J Hazard Mater. 2003 Jun 27;100(1-3):131-46. doi: 10.1016/s0304-3894(03)00070-0.
Aluminum sulfate, alum, is a common chemical coagulant used for coagulation. Recently, polymers have been utilized in coagulation/flocculation processes for water purification. In this study, the ability of two organic polymers, tannin (natural polyelectrolyte) and AN913 (synthetic anionic polyelectrolyte), and clay to act as coagulant aids was tested, in the removal of phosphate from synthetic wastewater. Contaminants in synthetic waters were coagulated using alum, alum+clay, alum+tannin, alum+AN913, alum+tannin+clay and alum+AN913+clay. Alum together with polymers as coagulant aids yielded a significant improvement in phosphate removal compared with alum alone, for initial phosphate concentrations of 5-15 mg/l PO(4)(3-). The use of clay and polyelectrolytes improved the efficiency of phosphate removal and lowered the required alum dose. Fourier transform infrared (FTIR) spectroscopy was used for the identification and characterization of the aluminum species formed during dephosphorization of the synthetic wastewater with and without tannin, AN913 and clay. Evidence from FTIR spectroscopy showed the formation of aluminum hydroxyphosphate, hydroxy-Al-tannate and aluminum complexes containing phosphorus, tannin and AN913.
硫酸铝，明矾，是一种用于混凝的常见化学混凝剂。近来，聚合物已被用于水净化的混凝/絮凝过程。在本研究中，测试了两种有机聚合物（单宁（天然聚电解质）和AN913（合成阴离子聚电解质））以及粘土作为助凝剂在去除合成废水中磷酸盐方面的能力。使用明矾、明矾+粘土、明矾+单宁、明矾+AN913、明矾+单宁+粘土和明矾+AN913+粘土对合成水中的污染物进行混凝。对于初始磷酸盐浓度为5 - 15 mg/l PO₄³⁻ 的情况，明矾与聚合物作为助凝剂一起使用时，与单独使用明矾相比，磷酸盐去除率有显著提高。粘土和聚电解质的使用提高了磷酸盐去除效率并降低了所需的明矾剂量。傅里叶变换红外（FTIR）光谱用于鉴定和表征在有或没有单宁、AN913和粘土的情况下合成废水脱磷过程中形成的铝物种。FTIR光谱的证据表明形成了羟基磷酸铝、羟基铝单宁酸盐以及含有磷、单宁和AN913的铝配合物。
