Sodium-dibenzyldithiocarbamate

Sodium dibenzyldithiocarbamate [55310-46-8] M295.4, m 230°(dec). The free acid when recrystd twice from dry Et2O has m 80-82°. The Na salt is reppted from aqueous EtOH or EtOH by addition of Et2O or Me2CO [AC 50 896 7975]. The NH4 salt has m 130-133° Cu salt (yellow crystals) has m 284-286° and the Ti salt has m 64-70°. 

Perkacil ETU. See Ethylene thiourea Perkacil MBS. See ISI-Oxydiethylene benzothiazole-2-sulfenamide Perkacil MBT. See 2-Mercaptobenzothiazole Perkacil MBTS. See Benzothiazyl disulfide Perkacil NDBC. See Nickel dibutyidithiocarbamate Perkacil SBEC. See Sodium dibenzyldithiocarbamate Perkacil SDBC. See Sodium di-n-butyl dithiocarbamate Perkacil SDEC. See Sodium diethyidithiocarbamate Perkacil SDMC. See Sodium dimethyidithiocarbamate Perkacii TBBS. See Butyl 2-benzothiazole sulfenamide... 

Sodium dibenzyldithiocarbamate 55335-06-3 Triclopyr 55353-19-0 Polyquaternium-10 55353-21-4 Resyn 28-2913 Resyn 28-2930... 

Separation and pre-concentration. A method first suggested by Knapp et al. (1975), developed further by Prange (1983) for seawater analysis using TXRF and later slightly modified by Schmidt et al. (1993) combines matrix removal with enrichment by a factor of about 50. The elements V, Mn, Fe, Co, Ni, Cu, Zn, Se, Mo, Cd, Pb and U are chelated using sodium-dibenzyldithiocarbamate (Na-DBDTC). The water-insoluble chelates are adsorbed on a column of a reversed-phase silica gel. Alkaline and alkaline earth elements elute unchelated with the aqueous phase and are discarded. The chelate complexes are removed from the dried column with a mixture of chloroform and methanol (methanol is needed for the quantitative elution of Mo). Some 100/tL of this extract are evaporated on quartz sample carriers and measured for around 1000 s. 

The buffer solution is prepared according to Section 12.4.2.4-Reagents. A solution is prepared of 400 mg of sodium dibenzyldithiocarbamate in 10 g of methanol. The solution can be stored, if cooled, for 1 or 2 days. A 2+1 (v v) mixture is prepared of CHQ3 and CH3OH. A dilution of a metal standard solution (e.g., 10mg/L Co) is prepared. 

Sodium-dibenzyldithiocarbamate (Na-DBDTC) tends to precipitate as carbamic acid at pH levels less than 4.8. Introduced into the column it accumulates at the column on its top and later redissolves in the CHCls CHsOH mixture, resulting in poor sample spots on the carrier. This leads to a large background signal and deterioration of the detection limits. Low lead and cadmium concentrations in open ocean water can be difficult or impossible to detect under such conditions. Thus, precipitation of carbamic acid must be avoided. 

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