灰化法磷测定中不同灰化助剂的效果比较——以磷酸氢二钠作为磷标样  

A COMPARISON OF EFFICIENCY OF DIFFERENT AUXILIARIES USED IN PHOSPHORUS DETERMINATION BY IGNITION METHOD WITH Na_2HPO_4 AS STANDARD PHOSPHORUS

作　　者：周毅[1] 张福绥[1] 杨红生[1] 马锡年[1] 

机构地区：[1]中国科学院海洋研究所,青岛266071

出　　处：《海洋科学》2002年第2期42-44,共3页Marine Sciences

基　　金：国家重点基础研究规划项目G1999012012号;中国科学院知识创新工程项目KZCX2 403号资助

摘　　要：对Na2HPO4 加入不同灰化助剂经不同温度 (150～550℃ )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 等十余种盐试剂进行了实验。作者认为 ,在利用目前已被广泛应用的由Sol幃ｒｚａｎｏ和Ｓｈａｒｐ１９８０年所提出的方法去分析海水中的颗粒磷和总磷或有机体中的磷时 ,应当用MgCl2 或Mg(Ac)2 作为灰化助剂而取代MgSO4。尽管Mg(NO3)2 也是高效的灰化辅助剂 。Researches on phosphorus recoveries from sodium orthophosphate dibasic (Na2HPO4) after ignition at temperatures from 200 to 550 ℃ with auxiliary, such as MgSO 4, Mg(NO 3)2, MgCl 2, MgAc 2, CaCl 2 and so on have been finished. The results indicate that the phosphorus can not be completely recovered when Na2HPO4 is ignited together with MgSO 4 at temperature not higher than 500 ℃ and with the final mixture extracted with 0.2 mol/L HCl at 25 ℃ for 1 h. In contrast, if Mg(NO 3)2, MgCl 2,MgAc 2,CaCl2 are added to Na 2HPO 4, the phosphorus recoveries can all get 100% in the same ignition temperatures(200-500 ℃) and extraction procedure. We suggest that MgCl2 (or MgAc 2) rather than MgSO 4 should be utilized as an ashing assistant in the phosphorus determination with ignition method. Although Mg(NO 3)2 is an highly effective auxiliary, yet danger of explosion, toxicity of nitrogen dioxide and more manipulation steps may impede its widespread utilization.

关 键 词：无机磷 灰化法测定 Na2HPO 灰化助剂 海水 磷标样 

分 类 号：P734.44[天文地球—海洋化学]