2-Nitrobenzaldehyde Thiocarbohydrazone Assisted Precise Extraction Spectrophotometric Method for the Determination of Ruthenium(III) in Alloy and Catalysts

A simple, rapid, selective, sensitive and reliable extractive spectrophotometric method was developed for the determination of ruthenium(III) using 2-nitrobenzaldehyde thiocarbohydrazone (2-NBATCH) as a chromogenic chelating ligand. The ruthenium(III)?2-NBATCH complex is formed in aqueous acetic acid media (0.7 M) containing an organic solvent after 5 min heating on a water bath. The red colored complex is extracted into 1,2-dichloroethane and absorbance is measured at 445 nm against reagent blank. The Beer’s law is obeyed within 1?6 g/mL of ruthenium(III), the optimum concentration range was 2?5 g/mL of ruthenium(III) evaluated by Ringbom’s plot. Molar absorptivity and Sandell’s sensitivity of complex were 1.41 × 10⁴ L/mol/cm and 0.0075 μg/cm², respectively. The stoichiometry of complex was 1: 3 established from Job’s method of continuous variation, molar ratio method and logarithmic slope method. The proposed method was applied for determination of ruthenium(III) in binary and ternary, synthetic mixtures corresponding to fission product elements alloy and ruthenium(III) catalysts.     

Development of a Liquid‐liquid Extraction System for Rhodium(III) by 2‐octylaminopyridine from Weak Malonate Media

We have developed the extraction method of rhodium(III) from malonate media with 2‐octylaminopyridine (2‐OAP) in xylene at pH 8.0. The quantitative extraction of rhodium(III) with extractant was found by screening of different physicochemical parameters like malonate concentration, extractant concentration, pH, diluents, effect of temperature, aq: org phase ratio, loading capacity of 2‐OAP. The optimum condition was malonate=0.025 M, pH=8.0, 2‐OAP=0.05 M in xylene. The complete stripping of rhodium(III) from the loaded organic phase was carried out with 2 M HCl. Log‐log plot was investigated to determine the stoichiometry of the extracted species and it was found to be 1 : 2 : 1 (metal : acid :extractant). The versatility of the proposed method was checked for extraction and separation of rhodium(III) from binary, ternary mixture of associated metal ions as well as platinum group metals and from the synthetic solution of rhodium minerals and alloys.     

Liquid–liquid extraction of uranium(VI) from weak sodium acetate medium using 2-octylaminopyridine: real sample analysis

Journal of Radioanalytical and Nuclear Chemistry - The analytical technique has been developed for the extraction and determination of uranium(VI). This process is based on the ion-pair complex...     

Development of liquid-liquid extraction and separation method for ruthenium(III) with 2-octylaminopyridine from succinate media: Analysis of catalysts

Ruthenium(III) has been efficiently extracted from 0.05 M sodium succinate at pH 9.5 by 2-octylaminopyridine in xylene and stripped with aqueous 10% (w/v) thiourea solution and determined spectrophotometrically. Various parameters viz., pH, weak acid concentration, reagent concentration, stripping agents, contact time, loading capacity, aq.: org. volume ratio, solvent has been thoroughly investigated for quantitative extraction of ruthenium(III). The utility of method was analyzed by separating the ruthenium(III) from binary mixture along with the base metals like Cu(II), Ag(I), Fe(II), Co(II), Bi(III), Zn(II), Ni(II), Se(IV), Te(IV), Al(III) and Hg(II) as well as platinum group metals (PGMs). Ruthenium(III) was also separated from ternary mixtures like Os(VIII), Pd(II); Pd(II), Pt(IV); Pd(II), Au(III); Pd(II), Cu(II); Fe(II), Cu(II); Ni(II), Cu(II); Co(II), Ni(II); Se(IV), Te(IV); Rh(III), Pd(II); Fe(III), Os(VIII). The stoichiometry 1: 2: 1 (metal: succinate: extractant) of the proposed complex was determined by slope analysis method by plotting graph of logD _[Ru(III)] versus logC _[2-OAP] and logD _[Ru(III)] versus logC _[succinate]. The interference of various cations and anions has been studied in detail and the statistical evaluations of the experimental results are reported. The method was successfully applied for the analysis of ruthenium in various catalysts, synthetic mixtures corresponding to the composition of alloys and minerals.