Activation Analysis of Manganese and Zinc in Sea Water1

Abstract

The use of activation analysis for the determination of microgram quantities of Mn and Zn in sea water was investigated.Total Mn and Zn were separated from the other elements of sea water by coprecipitation with iron as hydroxide, and divalcnt Mn and Zn were separated by extraction with diethyldithiocarbamate.Analyses were made from samples of water from different locations and depths of the North Pacific, Atlantic, and the Gulf of Mexico.Evidence indicates a substantial portion of Mn and Zn is held in sea water in a non-dialyzable and non-extractable form.INTRODUC '.lXON Increasing interest in trace elements in sea water makes it desirable to explore the application of sensitive radioactive methods to determine quantities in the micro and sub-microgram range. The presence of a wide variety of elements, over 40, imposes a very stringent requirement on the method of separation of trace elements from interfering elements, especially from the major components (sodium, chloride, magnesium, and bromine) and others which are prcscnt in comparatively large proportions. Induced activity of an element by thermal neutron bombardment and subsequent determination of the radioactive characteristics of a given element is sensitive as well as sclective. Activation analysis for the quantitative determination of Mn is especially favorable because of the high activation cross section of 13 x 1O-24 cm2 and relatively short half-

The accumulation from water of65Zn,54Mn,58Co and59Fe by the mussel,Mytilus edulis

“…Baric & Branica (1967) concluded that soluble zinc exists predominantly as Zn 2+ and possibly to a smaller extent as ZnOH+. Several authors (Rona et al 1962;Piro, 1970;Slowey & Hood, 1971) have reported on an organically complexed fraction. Piro, Verzi & Papucci (1969) and Piro (1970) discerned an ionic zinc content of 10-15 % and a particulate fraction of 35-40% of the total zinc content of sea water off La Spezia.…”

The Influence of Environmental Factors on the Sodium and Manganese Content of Barnacle Shells

“…In 6 samples more than 95% of the Mn was in suspension, These discrepancies no doubt reflect the well-known difficulties in defining dissolved and particulate for elements like Mn in natural waters (Livingstone 1963;Rona et al 1962). To avoid such confusion in terms, the Mn values in Fig.…”

Fulvic acid and aquatic manganese transport

“…The coordination chemistry of fulvic acid metal complexes is vague but could explain some of the observations that have appeared in the literature. Rona et al [1962] noted the presence of a nondialyzable manganese fraction in seawater. Barsdate and Alexander [1971] noted that much of the manganese in highly colored lake water was nondialyzable.…”