基于液相猿1P核磁共振的太湖水体溶解态磷富集方法优化研究

摘要

铝盐富集法是应用31 P核磁共振技术（31 P Nuclear magnetic resonance，31 P-NMR）分析水体溶解态磷组成的前处理方法。为将该方法更好地应用于太湖水体溶解态磷的研究中，针对铝盐添加时水体的pH 值、铝盐的添加量、提取剂的选择、水样体积等进行研究。结果表明，铝盐的添加量不仅和水体中溶解态总磷的浓度有关，也与富集水的体积相关；铝盐添加过程中，水体pH值会影响有机磷的去除率；太湖水体溶解态磷富集的最优方法是取过滤后的湖水20 L，添加3 g AlCl3·6H2 O并充分搅拌，且水体pH值保持6.0，静置过夜后，除去上覆水，收集含磷絮状物并离心，最后用0.5 mol/L NaOH+0.1 mol/L EDTA进行提取。%Phosphorus concentration with aluminum( Al)compound is a pretreatment method for the dissolved phosphorus analysis by 31 P-NMR. In order to apply this method to concentrating phosphor-us in freshwater of Lake Taihu,experiment conditions of this method were analyzed,including pH of water during Al precipitating dissolved phosphorus,amount of Al compound,volume of water and type of extractant. The results showed that the amount of Al compound needed in the phosphorus en-richment is related to not only the phosphorus concentration in freshwater,but also the volume of wa-ter. The best experiment conditions and procedures to concentrate phosphorus for 31 P-NMR analysis were selecting 20 L filtration water from Lake Taihu,and adding 3 g AlCl3 ·6H2O in the water (keeping pH value of 6. 0). After overnight,Al floc containing phosphorus was collected and then redissolved in 0. 5 mol·L-1 NaOH+0. 1 mol·L-1 EDTA.