ICP-MS DETERMINATION OF ULTRALOW CONTENTS OF URANIUM AND THORIUM IN ANTIQUE LEAD AFTER THEIR ISOLATION BY COUNTERCURRENT CHROMATOGRAPHY (LIQUID-CHROMATOGRAPHY WITH A FREE STATIONARY PHASE)

Natalia N Fedyunina ,Petr S Fedotov ,D.v Filosofov ,E Yakushev

doi:10.26896/1028-6861-2018-84-4-12-15

Abstract

A methodical approach to reduction of the limit of uranium and thorium detection in antique lead is proposed. The approach includes separation of the elements in the extraction system based on tetraphenylmethylene diphosphine dioxide and their subsequent ICP-MS determination. The influence of phase contact time, medium acidity, concentration of the extractant on the extraction of uranium and thorium from nitric acid solutions was studied under conditions of batch extraction. It is shown that the matrix element (lead) is not recovered in the considered extraction system. We specified and optimized conditions for concentration of uranium and thorium and their elution with an aqueous solution of etidronic acid using countercurrent chromatography. The content of uranium and thorium in the sample of antique lead raised from the ocean floor are less than 10 –10 % wt.

Highlights

ÎÏÐÅÄÅËÅÍÈÅ ÓËÜÒÐÀÍÈÇÊÈÕ ÑÎÄÅÐÆÀÍÈÉ ÓÐÀÍÀ È ÒÎÐÈß Â ÀÍÒÈ×ÍÎÌ ÑÂÈÍÖÅ ÌÅÒÎÄÎÌ ÌÀÑÑ-ÑÏÅÊÒÐÎÌÅÒÐÈÈ Ñ ÈÍÄÓÊÒÈÂÍÎ-ÑÂßÇÀÍÍÎÉ ÏËÀÇÌÎÉ ÏÎÑËÅ ÈÕ ÂÛÄÅËÅÍÈß ÌÅÒÎÄÎÌ ÆÈÄÊÎÑÒÍÎÉ ÕÐÎÌÀÒÎÃÐÀÔÈÈ ÑÎ ÑÂÎÁÎÄÍÎÉ ÍÅÏÎÄÂÈÆÍÎÉ ÔÀÇÎÉ1
The approach includes separation of the elements in the extraction system based on tetraphenylmethylene diphosphine dioxide and their subsequent ICP-MS determination
The influence of phase contact time, medium acidity, concentration of the extractant on the extraction of uranium and thorium from nitric acid solutions was studied under conditions of batch extraction

Summary

Introduction

ÎÏÐÅÄÅËÅÍÈÅ ÓËÜÒÐÀÍÈÇÊÈÕ ÑÎÄÅÐÆÀÍÈÉ ÓÐÀÍÀ È ÒÎÐÈß Â ÀÍÒÈ×ÍÎÌ ÑÂÈÍÖÅ ÌÅÒÎÄÎÌ ÌÀÑÑ-ÑÏÅÊÒÐÎÌÅÒÐÈÈ Ñ ÈÍÄÓÊÒÈÂÍÎ-ÑÂßÇÀÍÍÎÉ ÏËÀÇÌÎÉ ÏÎÑËÅ ÈÕ ÂÛÄÅËÅÍÈß ÌÅÒÎÄÎÌ ÆÈÄÊÎÑÒÍÎÉ ÕÐÎÌÀÒÎÃÐÀÔÈÈ ÑÎ ÑÂÎÁÎÄÍÎÉ ÍÅÏÎÄÂÈÆÍÎÉ ÔÀÇÎÉ1. Â óñëîâèÿõ ñòàòè÷åñêîé ýêñòðàêöèè èçó÷åíî âëèÿíèå âðåìåíè êîíòàêòà ôàç, êèñëîòíîñòè ñðåäû è êîíöåíòðàöèè ýêñòðàãåíòà íà èçâëå÷åíèå óðàíà è òîðèÿ èç àçîòíîêèñëûõ ðàñòâîðîâ. Ïîëó÷åííûå ðåçóëüòàòû ïîçâîëèëè âûáðàòü è îïòèìèçèðîâàòü óñëîâèÿ êîíöåíòðèðîâàíèÿ óðàíà è òîðèÿ è èõ ýëþèðîâàíèÿ âîäíûì ðàñòâîðîì ýòèäðîíîâîé êèñëîòû â ðåæèìå æèäêîñòíîé õðîìàòîãðàôèè ñî ñâîáîäíîé íåïîäâèæíîé ôàçîé. Óñòàíîâëåíî, ÷òî ñîäåðæàíèå óðàíà è òîðèÿ â îáðàçöå àíòè÷íîãî ñâèíöà, ïîäíÿòîãî ñî äíà îêåàíà, íàõîäèòñÿ íà óðîâíå íèæå 10–10 % ìàññ.

Results

Conclusion