Ammonium Pyrollidine Dithiocarbamate Research Articles

A novel method for the estimation of cobalt (II) in practical samples using ammonium pyrollidine dithiocarbamate

AbstractAn easy and quick spectrophotometric method was developed and employed for detection and quantification of cobalt using ammonium pyrollidine dithiocarbamate (APDC) in presence of anionic surfactant sodium dodecyl sulfate aqueous micellar solution. The cobalt forms bis(ammonium pyrollidine dithiocarbamato) cobalt complex reacting with ammonium pyrollidine dithiocarbamate. The prepared complex was used for the detection of Co(II) ions spectrophotometrically in different types of samples of practical nature and developed methods shows high sensitivity and selectivity toward Co(II) ions and the coefficient of molar absorption (ε) and Sandell's sensitivity were 2.35 × 104 L mol−1 cm−1 and 2.73 ng/cm2 at λmax 322.2 nm, respectively. A linear relationship with concentration was observed in the range of 0.12–4.0 μg/ml and 1:2 metal to ligand ratio was found best for the complex Co–[APDC]2 formation. Using developed material and method, cobalt ions in pharmaceutical, tap water and reference material was recovered up to 99.81, 99.0, and 99.14 (%), respectively. The developed methods has potential for Co(II) estimation and could possibly be used for Co(II) quantification in practical samples.

Qualitative analysis of Cu2+, Co2+, and Ni2+ cations using thin-layer chromatography.

The M(DEDTC)2 (M = Cu, Co, or Ni) and M(PyDTC)2 (M = Cu or Co) complexes prepared by reactions of sodium diethyldithiocarbamate and ammonium pyrollidinedithiocarbamate with metal (II) nitrates are examined for qualitative analysis and separation using thin-layer chromatography systems. These complexes and their mixtures are spotted to the activated thin layers of silica gel 60GF254 (Si-60GF254) with a 250-microm thickness. Pure toluene and a toluene-cyclohexane mixture (3:1, v/v) are used as mobile phases for running of the complexes. These chromatographic systems are successfully used for qualitative analysis of corresponding metal cations and separation of components in both M(DEDTC)2 and M(PyDTC)2 complex mixtures.

Speciation analysis of inorganic Sb(III) and Sb(V) ions by using mini column filled with Amberlite XAD-8 resin

The speciation of inorganic Sb(III) and Sb(V) ions in aqueous solution was studied. The adsorption behavior of Sb(III) and Sb(V) ions were investigated as iodo and ammonium pyrollidine dithiocarbamate (APDC) complexes on a column filled with Amberlite XAD-8 resin. Sb(III) and Sb(V) ions were recovered quantitatively and simultaneously from a solution containing 0.8M NaI and 0.2M H2SO4 by the XAD-8 column. Sb(III) ions were also adsorbed quantitatively as an APDC complex, but the recovery of the Sb(V)–APDC complex was found to be <10% at pH 5. According to these data, the concentrations of total antimony as Sb(III)+Sb(V) ions and Sb(III) ion were determined with XAD-8/NaI+H2SO4 and XAD-8/APDC systems, respectively. The Sb(V) ion concentration was calculated by subtracting the Sb(III) concentration found with XAD-8/APDC system from the total antimony concentration found with XAD-8/NaI+H2SO4 system. The developed method was applied to determine Sb(III) and Sb(V) ions in samples of artificial seawater and wastewater.

Rapid Determination of Zinc in Saline Waters

A rapid, precise and sensitive solvent extraction-atomic spectrometric technique has been developed for the determination of dissolved zinc in saline waters, using a well established solvent extraction-flame atomic absorption spectrometry method (ammonium pyrollidine dithiocarbamate — methyl isobutyl ketone). The concentration range of the technique covers levels found in estuarine and coastal waters for analytical batches of 22 samples. The limit of detection of the technique is estimated as 0.7 μg L−1. Data for spiking recovery and long term standard deviation of determination are presented.

Determination of total cadmium in calcareous soils by extraction using aliquat‐336 and 3‐heptan‐one after aqua regia digestion

Abstract Measurement of total soil cadmium (Cd) is difficult due to calcium (Ca) and other chemicals which cause high background absorbance when trace levels of Cd are to be determined. When soil Cd is low, even use of deuterium background correction with flame atomic absorption spectroscopy (AAS) cannot provide accurate Cd results. Use of furnace atomic absorption with method of standard additions can circumvent these interferences, but the cost and time required are substantial. We desired a more rapid, convenient, and reliable alternative to extraction using dithizone and back‐extraction into acid, or to ammonium pyrollidinedithiocarbamate (APDC) which does not require close pH adjustment nor have many sources of potantial contamination. We evaluated analysis of these complex soil extracts with the method of Viets (1978) which extracts metals from 1N acid solutions using Aliquat‐336 in methylisobutyl‐ketone (MIBK). We tested the use of the less toxic and less water soluble 3‐heptanone as an organic sol...

An analytical method for hydrogeochemical surveys: Inductively coupled plasma-atomic emission spectrometry after using enrichment coprecipitation with cobalt and ammonium pyrrolidine dithiocarbamate

Trace metals that are commonly associated with mineralization were concentrated and separated from natural water by coprecipitation with ammonium pyrollidine dithiocarbamate (APDC) and cobalt and determined by inductively coupled plasma-atomic emission spectroscopy (ICP-AES). The method is useful in hydrogeochemical surveys because it permits preconcentration near the sample sites, and selected metals are preserved shortly after the samples are collected. The procedure is relatively simple: (1) a liter of water is filtered; (2) the pH is adjusted; (3) Co chloride and APDC are added to coprecipitate the trace metals; and (4) later, the precipitate is filtered, dissolved, and diluted to 10 ml for a 100-fold concentration enrichment of the separated metals. Sb(III), As(III), Cd, Cr, Cu, Fe, Pb, Mo, Ni, Ag, V, and Zn can then be determined simultaneously by ICP-AES. In an experiment designed to measure the coprecipitation efficiency, Sb(III), Cd and Ag were recovered at 70 to 75% of their original concentration. The remaining metals were recovered at 85 to 100% of their original concentrations, however. The range for the lower limits of determination for the metals after preconcentration is 0.1 to 3.0 μg/l. The precision of the method was evaluated by replicate analyses of a Colorado creek water and two simulated water samples. The accuracy of the method was estimated using a water reference standard (SRM 1643a) certified by the U.S. National Bureau of Standards. In addition, the method was evaluated by analyzing groundwater samples collected near a porphyry copper deposit in Arizona and by analyzing meltwater from glacier-covered areas favorable for mineralization in south-central Alaska. The results for the ICP-AES analyses compared favorably with those obtained using the sequential technique of GFAAS on the acidified but unconcentrated water samples. ICP-AES analysis of trace-metal preconcentrates for hydrogeochemical surveys is more efficient than GFAAS because a large suite of metals is simultaneously determined with acceptable analytical accuracy and precision. The proposed analytical technique can provide direct evidence of mineralization and is useful in the exploration for unknown ore deposits.

Storage and processing of estuarine water samples for trace metal analysis by atomic absorption spectrometry

Saline water samples from the Delaware Bay estuary were sampled, processed, and stored in a variety of ways to allow different methods of maintaining their integrity to be compared. Samples were processed onboard ship, immediately after collection, by extraction with ammonium pyrollidinedithiocarbamate in methyl isobutyl ketone. Duplicate samples were processed onshore after a variety of storage procedures. All samples were analyzed for copper and iron by atomic absorption spectrometry. Only samples filtered (<1 μm), acidified, and stored frozen gave extractable copper and iron results comparable with those for samples extracted immediately after collection. Cold storage with sample acidification in polyethylene containers appeared less satisfactory. Organic extracts from samples processed onboard are best retained in all-Teflon containers pending complete digestion and analysis onshore. Unless clean (ultra-filtered air) conditions can be ensured onboard, the estuarine water samples are best returned in a filtered, acidified, and frozen condition for onshore processing.

Sources of error in the determination of Cd and Pb in plant material by atomic absorption

Abstract Some difficulties were met when low levels of Cd and Pb were estimated in plant samples in this laboratory by atomic absorption spectrophotometry (AAS). A modified procedure, based on methyl isobutyl ketone (MIBK) extraction of the metal complexes with ammonium pyrollidine dithio carbamate (APDC), has been developed for use on samples digested with HNO3/HCIO4. The procedure was compared with X‐ray fluorescence and with other AAS methods including those based on dry ashing. Dry ashing gave generally lower values for Cd and Pb. Improvement in conditions of digestion and analysis are described. Of these, the presence of small amounts of Fe in standards and unknown samples increases the stability and reproducibility of absorbance values, especially for cadmium.

Trace elements in the interstitial waters of marine sediments

Phosphate and eleven elements were determined in the interstitial waters of four piston cores from the continental borderland area off the coast of Southern California. Calcium, magnesium, potassium, sodium and strontium were determined directly by atomic absorption spectrophotometry. Phosphate was determined colorimetrically and the trace elements: cadmium, cobalt, copper, iron, nickel and zinc, were determined by extraction of the chelate complexes with ammonium pyrollidine dithiocarbamate into methylisobutyl ketone and subsequent analysis by atomic absorption spectrophotometry. Correlation coefficients for various pairs of variables are given. Decrease of Eh and increase of phosphate with depth was attributed mainly to bacterial activity and in the case of phosphate, partly due to release from metal phosphates. Calcium and strontium showed decreases with depth probably due partly to precipitation of carbonate by excess bicarbonate ions produced as a result of bacterial activity and partly to precipitation as phosphate. Potassium levels were higher and magnesium values were slightly lower than in sea water, probably due to interaction with the solid phase of the sediments. Copper showed no overall trends, but zinc showed moderate decrease with depth and correlated well with cadmium. Enrichment of cobalt, zinc, cadmium and copper at the surface of the sediments was attributed to biological concentration, and release, since there is more than sufficient organic matter present to account for such a source. Iron and nickel concentrations were greater in reducing sediments and showed an overall trend to increase with depth.

APDC-MIBK extraction system for the determination of trace elements in saline waters by atomic-absorption spectrophotometry

A technique has been developed for the determination of “soluble” cobalt, copper, iron, lead, nickel and zinc in saline waters by simultaneous extraction of their complexes with ammonium pyrollidine dithiocarbamate (APDC) into methyl isobutyl ketone (MIBK) and subsequent analysis by atomic-absorption spectrophotometry. Particulate matter is analysed separately by dissolving millipore filters in an acetone-hydrochloric acid mixture. Various analytical and instrumental parameters have been evaluated. The method is selfcompensating in that it makes allowance for any incomplete extraction of the complexes. The technique has been applied to the determination of these elements in sea-water and saline lakes.

Determination of copper in saline waters by atomic absorption spectrohotometry combined with apdc-mibk extraction

A technique has been developed for the determination of copper in saline waters by extraction of its complex with ammonium pyrollidine dithiocarbamate into methyl isobutyl ketone and subsequent analysis by atomic absorption spectrophotometry. The method is self-compensating for any incomplete extraction of copper. With a 15:510 solvent-aqueous phase ratio, a sensitivity of 0.2 p.p.b. and a precision of ±10% were achieved. The method was used to determine copper in a number of sea water and other'saline water samples.

The determination of trace quantities of molybdenum by atomic absorption spectroscopy

A procedure is described for the determination of trace quantities of molyb denum by atomic absorption spectroscopy. Molybdenum is cornplexed with ammoni um pyrollidine dithiocarbamate or 8-hydroxyquinoline and extracted into n-amyl methyl ketone. Molybdenum is then determined by atomic absorption spectroscopy. Interferences have been eliminated and detection limits of 0.002 p.p.m, for water samples, 0.1 p.p.m. for samples of dried plant material, and 1 p.p.m. for silicate rock samples have been obtained.