餐厨垃圾渗滤液中全磷、全钾和总钠的测定

Determination of total phosphorus,total potassium and total sodium in food waste leachate

建立电热石墨消解-电感耦合等离子体发射光谱法(ICP-OES)测定餐厨垃圾渗滤液中全磷、全钾和总钠的测定方法。称样量为0.5 g餐厨垃圾渗滤液样品,加入3 mL浓硝酸及1.5 mL 30%过氧化氢,电热石墨消解温度为135℃,消解时间为100 min,采用ICP-OES法进行测定。结果表明:3种元素的质量浓度在0—20 mg∕L与光谱强度线性关系良好,相关系数(r^(2))均不小于0.9990,磷、钾和钠的检出限分别为2.14 mg∕kg、2.68 mg∕kg和1.94 mg∕kg。该方法对3个餐厨垃圾渗滤液样进行测定,全磷、全钾和总钠测定结果的相对标准偏差为1.8%—3.4%,加标回收率为97.8%—101.7%。电热石墨消解法测定结果与湿法消解无明显差异。该方法可快速测定餐厨垃圾渗滤液中全磷、全钾和总钠。

A method for the determination of total phosphorus,total potassium and total sodium in food waste leachate by electrothermal graphite digestion inductively coupled plasma atomic emission spectrometry(ICPOES)was established.Food waste leachate sample weigh was 0.5 g,added 3 mL concentrated nitric acid and 1.5 mL 30%hydrogen peroxide,electrothermal graphite digestion temperature was 135℃,digestion time was 100 min,and determined the samples by ICP-OES.The results showed that the mass concentrations of the three elements have a good linear relationship with the spectral intensity in the range of 0—20 mg∕L,the correlation coefficient(r^(2))was not less than 0.9990,and the detection limits of phosphorus,potassium and sodium were 2.14 mg∕kg,2.68 mg∕kg and 1.94 mg∕kg respectively.The relative standard deviations of total phosphorus,total potassium and total sodium were 1.8%—3.4%,and the recoveries were 97.8%—101.7%.There was no significant difference between electrothermal graphite digestion and wet digestion.The method can quickly determine total phosphorus,total potassium and total sodium in food waste leachate.