生物除磷颗粒污泥去除Pb2+的效能机制

以好氧颗粒污泥的吸附作用和磷酸盐对重金属的螯合作用为基础，采用富含磷酸盐的生物除磷颗粒污泥作为吸附剂来处理含铅废水，考察了不同吸附条件（pH、Pb²⁺的初始浓度、吸附反应时间）下，颗粒污泥对Pb²⁺的去除效果。结果表明，除磷颗粒污泥在pH为4，初始Pb²⁺浓度为150 mg·L^-1时，对铅的去除率最高（为99.9%）；在吸附反应20 min时即可达到吸附平衡。生物除磷颗粒污泥对Pb²⁺的吸附可以用Langmuir模型拟合（R²=0.993），最大吸附量为49.5 mg·g^-1。其中离子交换和磷酸盐与Pb²⁺的螯合作用对除磷颗粒污泥去除Pb²⁺起到重要作用；傅里叶变换红外光谱（FTIR）测定表明-COOH、-OH、磷酰基等多种官能团也参与了除磷颗粒污泥除Pb²⁺过程。

Performance and mechanism of Pb2+ removal by phosphorus removal granular sludge

In this study, based on the adsorption of aerobic granular sludge and the chelating action of phosphate on heavy metals, phosphate containing biological phosphorus removal granular sludge was used as adsorbent to treat Pb²⁺ containing wastewater, and the removal efficiency of Pb²⁺ by granular sludge under different adsorption conditions was investigated. The results showed that the highest removal efficiency of Pb²⁺ (up to 99.9%) was achieved under the optimal adsorption conditions (pH=4 and the initial concentration of Pb²⁺ 150 mg·L^-1), and the adsorption equilibrium reached in 20 min. The adsorption of Pb²⁺ by biological phosphorus removal granular sludge can be described by Langmuir model. The correlation coefficient R² was 0.993, and the maximum adsorption quantity was about 49.5 mg·g^-1. Ion exchange and chelation of phosphate with Pb²⁺ played a significant role in the removal of Pb²⁺ by using the phosphorus removal granular sludge. The results of Fourier transform infrared spectroscopy (FTIR) indicated that a variety of functional groups such as -COOH,-OH and phosphoryl were involved in the removal of Pb²⁺ by phosphorus removal granular sludge.