Cadmium dithiocarbamates

Dithiocarbamates, especially those of zinc, are well known and have important industrial applications as antioxidants/antiabrasives in motor oils and as vulcanization accelerators in rubber. They are normally dimerized as in 15-VIII, thereby giving each zinc atom a distorted trigonal bipyramidal coordination.51 Zn(Me2dtc)2 is dimerized in a different way, 15-IX, but vaporizes as monomers.52 Both zinc and cadmium dithiocarbamates are cleaved by monoamines to give 5-coordinate... 

Cadmate . [R.T. Vanderbilt] Cadmium dithiocarbamates accelerator for natural and polyist uene rubbers. 

EXTRACTION AND DETERMINATION OF LEAD, CADMIUM, AND COPPER USING AMMONIUM PYROLLIDINE DITHIOCARBAMATE... 

The structural chemistry of some metal dithiocarbamates, i.e. systematics, coordination modes, crystal packing, and supramolecular self-assembly patterns of nickel, zinc, cadmium, mercury,363 organotin,364 and tellurium,365 366 complexes has been thoroughly analyzed and discussed in detail. Supramolecular self-assembly frequently occurs in non-transition heavier soft metal dithiocarbamates. Thus, lead(II),367 bismuth(III)368 zinc,369 cadmium,370 and (organo)mercury371 dithiocarbamates are associated through M- S secondary bonds, to form either dimeric supermolecules or chain-like supramolecular arrays. The arsenic(III)372 and antimony(III)373 dithiocarbamates are... 

Cabezon et al. [662] simultaneously separated copper, cadmium, and cobalt from seawater by coflotation with octadecylamine and ferric hydroxide as collectors prior to analysis of these elements by flame atomic absorption spectrometry. The substrates were dissolved in an acidified mixture of ethanol, water, and methyl isobutyl ketone to increase the sensitivity of the determination of these elements by flame atomic absorption spectrophotometry. The results were compared with those of the usual ammonium pyrrolidine dithiocarbamate/methyl isobutyl ketone extraction method. While the mean recoveries were lower, they were nevertheless considered satisfactory. 

Jin [666] used ammonium pyrrolidine dithiocarbamate and electrothermal atomic absorption spectrometry to determine lead, cadmium, copper, cobalt, tin, and molybdenum in seawater. 

Cadmium, copper, and silver have been determined by an ammonium pyrrolidine dithiocarbamate chelation, followed by a methyl isobutyl ketone extraction of the metal chelate from the aqueous phase [677], and finally followed by graphite furnace atomic absorption spectrometry. The detection limits of this technique for 1% absorption were 0.03 pmol/1 (copper), 2 nmol/1 (cadmium), and 2 nmol/1 (silver). 

Ammonium pyrrolidine dithiocarbamate (APDC) chelate coprecipitation coupled with flameless atomic absorption provides a simple and precise method for the determination of nanomol kg 1 levels of copper, nickel, and cadmium in seawater. With practice, the method is not overly time-consuming. It is reasonable to expect to complete sample concentration in less than 20 min, digestion in about 4 h, and sample preparation in another hour. Atomic absorption time should average about 5 min per element. Excellent results have been obtained on the distribution of nickel and cadmium in the ocean by this technique. 

Bruland et al. [122] have shown that seawater samples collected by a variety of clean sampling techniques yielded consistent results for copper, cadmium, zinc, and nickel, which implies that representative uncontaminated samples were obtained. A dithiocarbamate extraction method coupled with atomic absorption spectrometry and flameless graphite furnace electrothermal atomisation is described which is essentially 100% quantitative for each of the four metals studied, has lower blanks and detection Emits, and yields better precision than previously published techniques. A more precise and accurate determination of these metals in seawater at their natural ng/1 concentration levels is therefore possible. Samples analysed by this procedure and by concentration on Chelex 100 showed similar results for cadmium and zinc. Both copper and nickel appeared to be inefficiently removed from seawater by Chelex 100. Comparison of the organic extraction results with other pertinent investigations showed excellent agreement. 

A poly(acrylaminophosphamic-dithiocarbamate) chelating fibre hasbeen used to preconcentratrate several trace metals in seawater by a factor of 200 [957]. The elements included beryllium, bimuth, cobalt, gallium, silver, lead, cadmium, copper, manganese, and indium. ICP-MS was used for detection. 

Cadmium Extraction of ammonium pyrrolidine dithiocarbamate complex with chloroform AAS 0.0006 xg/l [134,863]... 

Apte and Gunn [23] used liquid-liquid extraction, involving 1 1 1 trichlor-ethane extraction of the ammonium pyrrolidine dithiocarbamates to concentrate copper, nickel, lead, and cadmium from estuary water. (Detection limits... 

Clem and Hodgson [27] discuss the temporal release of traces of cadmium and lead in bay water from EDTA, ammonium pyrollidine-dithiocarbamate, humic acid and tannic acid after treatment of the sample with ozone. Anodic scanning voltammetry was used to determine elements. 

Block, M. and Part, P. (1986). Increased availability of cadmium to perfused rainbow trout (Salmo gairdneri, Rich) gills in the presence of the complexing agents diethyl dithiocarbamate, ethyl xanthate and isopropyl xanthate, Aquat. Toxicol., 8, 295-302. 

Extractable cadmium in soil has been determined by extraction with 0.5 M acetic acid followed by extraction with a chloroform solution of pyrrolidine dithiocarbamate, then decomposition of the cadmium complex with hydrochloric acid and determination of cadmium by atomic absorption spectrometry at 228.8 nm [49]. 

These techniques have crossovers in the sense that, for example, LCVD can be done with metal-organic precursors. Cheon and Zink (1997) deposited thin films of ZnS, CdS, and Zn,Cdi S onto quartz substrates. The source of the metal and the sulfur was the organometallic compound diethyl dithiocarbamate zinc or cadmium M(S2CNEt2)2- In this case a single precursor was used to produce a binary compound as a thin film. 

I. Narin, M. Soylak, Enrichment and determinations of nickel (II), cadmium(II), copper(II), cobalt(II), and lead(II) ions in natural waters, table salts, tea and urine samples as pyrrolydine dithiocarbamate chelates by membrane filtration-flame atomic absorption spectrometry combination, Anal. Chim. Acta, 493 (2003), 205-212. 

CADMIUM, BIS(PENTYLDITHIOCARB.AMATO)- CADMIUM DIAMYL DITHIOCARBAMATE... 

CADMIUM DIAMIDE see CAD325 CADMIUM DIAMYL DITHIOCARBAMATE see CAD550... 

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