Determination of trace levels of heavy metals in waters by extraction with ammonium tetramethylenedithiocarbamate and hexamethyleneammonium hexamethylenedithiocarbamate into xylene followed by inductively-coupled plasma emission spectrometry

Assessment of water quality of Manchar Lake in Sindh (Pakistan)

“…The latter includes 'ion exchange' (Kiriyama and Kuroda 1988), 'co-precipitation' (Elci et al 1997;Atanassova et al 1998), 'evaporation' (Hudnik et al 1978) and 'freeze drying' (Hjorth 2004). In preconcentration, various chelating agents have been used (Gomez-Ariza et al 1976;Smith and Windom 1980;Tao et al 1984;Nojiri et al 1985); however, picolinaldehyde 4-phenyl-3-thiosemicarbazone (PAPT) has been reported as the most efficient chelating agent for selective determination of trace metals (Gomez-Ariza et al 1976). …”

Spectrophotometric catalytic determination of an ultratrace amount of iron(III) in water based on the oxidation of N,N-dimethyl-p-phenylenediamine by hydrogen peroxide

“…Recently, there has been an increasing need for a highly sensitive method of analysis for iron in water surveys and in environmental and biochemical studies. Many of the following instrumental methods of analysis for iron have been proposed: spectrophotometry (1)(2)(3)(4)(5)(6), amperometry (7), atomic absorption spectrometry (8)(9)(10)(11)(12), and inductively coupled plasma atomic emission spectrometry (13)(14)(15)(16). Most of them, however, lack sufficient sensitivity for determining iron in water samples at nanogram-or sub-nanogram-per-milliliter levels.…”

Affinity Extraction into CO2. 2. Extraction of Heavy Metals into CO2 from Low-pH Aqueous Solutions

“…4,[11][12][13][14][15][16][17][18][19] The extraction of chromium has been investigated previously by a number of groups. [14][15][16][17][18][26][27][28] In most cases, Cr 3+ was converted into Cr 6+ by preoxidation before the complexing procedure. APDC, either alone or in combination with other chelating agents, was employed in chromium extraction at pH's ranging from 1 to 7, but most of them could not achieve effective extraction.…”