Application of the reaction system methylene blue b-[.sub.2][S.sub.2][O.sub.8] za kineticko spektrofotometrijsko odredivanje paladijuma u citratnom puferu

• Published in: Hemijska industrija
• Main Authors: Rancic, Sofija M, Nikolic-Mandic, Snezana D, Bojic, Aleksandar Lj, Doric-Veljkovic, Snezana M, Zarubica, Aleksandra R, Jankovic, Predrag Lj
• Format: Journal Article
• Language: English
• Published: Association of Chemical Engineers of Serbia 01.01.2016
• Subjects: Chemical properties; Chemical reactions; Identification and classification; Methods; Methylene blue; Observations; Palladium; Spectrophotometry
• ISSN: 0367-598X; 2217-7426

A new, simple, rapid, sensitive and selective kinetic spectrophotometric method for Pd(II) traces determination was elaborated in this paper. It is based on the catalytic effect of palladium ions upon the oxidation of methylene blue B(MBB) by [(N[H.sub.4]).sub.2][S.sub.2][O.sub.8] (APS) in citric buffer(BUF) solution. At the working temperature of 25°C and the wave length of 662.4 nm, the optimal conditions for palladium determination were found. RSD value was found to be 2.6 to 4.9% for the investigated concentration range of Pd(II). Limit of detection(LD) was found to be 2.0 ng [cm.sup.-3] Pd(II), and limit of quantification(LQ) is 6.9 ng [cm.sup.-3] Pd(II). Only the presence of [Pb.sup.2+], [Hg.sup.2+] and [Sn.sup.2+] in the reaction mixture interferes the determination of palladium by this method, while Au 3+ and [Ag.sup.+] have the catalytic effect upon the reaction rate. By this method, it is possible to determine the Pd(II) traces in the concentration range of 3.3*[10.sup.-8] to 1.0*[10.sup.-6] g [cm.sup.-3] .The method was confirmed by determination of Pd(II) traces in alloy PtRhG as well as in the powder of Pt. The obtained results were compared to those obtained by ICP-OES method and good agreement of results was found. U ovom je radu predstavljena nova kinetickaspektrofotometrijska metoda za odredivanje tragova paladijuma u rastvoru, zasnovana na katalitickom dejstvu Pd(II) jona na reakciju oksidacije metilen plavog B(MBB) amonijum persulfatom(APS) u citratnom puferu(BUF). Upotrebom lako dostupne opreme i ralativno jeftinih hemikalija, na temperaturi od 25°C i talasnoj duzini od 662.4 nm, odredeni su optimalni uslovi za proticanje reakcije i ostvareni precizni i reproduktivni rezultati. RSD je u rasponu od 2.6-4.9% za ispitivanu oblast koncentracija Pd(II). Ovom metodom je moguce odredivato paladijum u interval koncentracija od 3.3*[10.sup.-8] do 1.0*[10.sup.-6] g [cm.sup.-3]. Na osnovu dobijenih rezultata se moze zakljuciti, da nova kineticka metoda pokazuje vrlo dobru selektivnost. Naime, samo prisustvo [Pb.sup.2+], [Hg.sup.2+] i [Sn.sup.2+] u reakcionoj smesi, ometa odredivanje paladijuma ovom metodom, dok ga prisustvo [Au.sup.3+] i [Ag.sup.+], katalizuje. Odredena je granica kvantifikacije (LQ) od 6.9 ng[cm.sup.-3] Pd(II), kao i granica detekcije (LD) od 2.0 ng [cm.sup.-3] Pd(II). LQ je definisana kao odnos signal:sum = 10:1 and LD kao signal 3:1 u odnosu na slepu probu. Primenom kineticke i ICP-OES metode, kao referentne, za odredivanje paladijuma u uzorcima legure PtRhG i prahu platine i poredenjem dobijenih rezultata, moze se zakljuciti da je nova kineticka spektrofotometrijsko metoda pogodna za odredivanje Pd(II) u legurama i metalurskim uzorcima, a potencijalno i u drugim uzorcima iz proizvodnih procesa i zivotne sredine. Takode, rezultati ispitivanja ukazujuna to da ona moze da bude dobra osnova za dalja istrazivanja u oblasti razvoja kinetickih metoda analize. Keywords: Pd(II) determination, catalyst, kinetic spectrophotometric method Kljucne reci: odredivanjePd(II), katalizator, kineticko spektrofotometrijskametoda