灰化法磷测定中不同灰化助剂的效果比较:以焦磷酸钠作为磷标样  

A comparison of efficiency of different assistants used in phosphorus determination by ignition method with Na_4p_2O_7 as standard phosphorus

作　　者：周毅[1] 张福绥[1] 马锡年[1] 杨红生[1] 何义朝[1] 

机构地区：[1]中国科学院海洋研究所,山东青岛266071

出　　处：《海洋学报》2001年第5期58-64,共7页

基　　金：国家重点基础研究规划资助项目 (G19990 12 0 12 ) ;中国科学院知识创新工程资助项目 (KZCX2 - 40 3) ;国家重点科技资助项目 (96 - 92 2 - 0 2 - 0 4) .

摘　　要：对Na4P2 O7加入不同灰化助剂经不同温度 ( 2 0 0～ 550℃ )灼烧后磷的回收率进行了研究 .所研究的灰化助剂除文献中已深入研究过的MgSO4和Mg(NO3) 2 外 ,还对MgCl2 等 1 0余种盐试剂进行了实验 .结果表明 ,除Mg(NO3) 2 外 ,MgCl2 ,MgAc2 ,CaCl2 ,Ca(NO3) 2 等均能使Na4P2 O7灰化后的磷完全回收 (灼烧温度不低于 450℃ ) ,而加入MgSO4在任何灼烧温度下磷的回收率均低于 80 % ,效果不佳 .因此 ,在利用目前已被广泛应用的由Sol幃ｒｚａｎｏ和Ｓｈａｒｐ所提出的方法去分析篕械目帕A缀妥芰谆蛴谢逯械牧资?,应当用MgCl2 (或MgAc2 )作为灰化助剂来取代MgSO4.Researches on phosphorus recoveries from sodium pyrophosphate (Na 4P 2O 7) after ignition at temperature from 200 to 550 ℃ with auxiliary, such as MgSO 4, Mg(NO 3) 2, MgCl 2, MgAc 2, CaCl 2, Ca(NO 3) 2 and so on, are finished. The results indicate that MgSO 4 gives poor phosphorus recovery at any ignition temperature from 200 to 550 ℃, when the final residue is extracted with 0.2 mol/dm 3 HCl at 80 ℃ for 30 min. By contrast, Mg(NO 3) 2, MgCl 2, MgAc 2, CaCl 2 and Ca(NO 3) 2 give very good phosphorus recovery with ignition temperature being equal to or greater than 450 ℃.It is suggested that MgCl 2 (or MgAc 2) rather than MgSO 4 can be used as ashing assistant in the phosphorus determination by ignition method.

关 键 词：磷测定 灰化法 灰化助剂 灼烧温度 焦磷酸钠 回收率 海水分析 

分 类 号：P734.41[天文地球—海洋化学]