EDTA as Masking Agent in Selective Spectrophotometric Determination of Copper with Triethylenetetramine. An Interpretation of Masking.

Abstract

RCA laboratories, Princeton, N. J.b The blue colored copper triethenetetramine complex formed at pH 10 in the presence of EDTA and tartrate offers a highly selective method for determining copper in the milligram range. Variables for the color development have been studied. Many anions do not interfere; however the halides enhance the absorbance of the copper trietbenetetramine complex in the order F-< CI-< Br-< I-. pH plays an important role in masking; from the point of view of competing equilibria, the masking action of EDTA is theoretically interpreted. Further possibilities of using masking agents and other polyamines for the spectrophotometric determination of nickel and cobalt are indicated. URING THE LAST DECADE, several

A Fiber-Optic Sensor for Monitoring Trace Ammonia in High-Temperature Gas Samples With a ${\hbox{CuCl}}_{2}$-Doped Porous Silica Optical Fiber as a Transducer

“…As indicated in these spectra, the peak absorption wavelength of the formed complex in the porous silica optical fiber is around 545 nm. The observed peak absorption wavelength of Cu NH complex in this experiment is different from that of Cu NH complex in aqueous solutions reported in traditional UV/Vis absorption spectrometry [24]. One potential explanation for this difference is that the complex formed in the porous silica optical fiber of this paper is different from that formed in an aqueous solution in traditional UV/Vis spectrometry.…”

“…In an aqueous solution with excess of NH , the reaction Cu NH Cu NH (1) yields an equilibrium constant (K) K Cu NH Cu NH (2) equal to 3.9 10 [23]. The resulting complex in an aqueous solution shows a blue color and absorbs light with a peak absorption wavelength at around 560 nm [24]. This complex reaction has been used in traditional UV/Vis absorption spectrometry for the determination of copper ions in aqueous solutions through the addition of excess NH into a sample solution [24].…”

Determination of the Cation Exchange Capacity (CEC) of Clay Minerals Using the Complexes of Copper(II) Ion with Triethylenetetramine and Tetraethylenepentamine

“…The maximum light extinction for these complexes varies slightly in the pH range of 5-10. The maximum absorption is not affected by other cations or anions at low salt concentration (Cheng, 1962). Compared to other methods the Cu(II) complexes with triethylenetetramine and tetraethylenepentamine allow an easy and rapid CEC determination by photometric analysis.…”

Optical Fiber Chemical Sensor with Sol-Gel Derived Refractive Material as Transducer for High Temperature Gas Sensing in Clean Coal Technology

“…As indicated in these spectra, the peak absorption wavelength of the formed complex in the sol-gel silica optical fiber is around 540 nm. The observed difference in the peak absorption wavelength of the complex in a sol-gel silica optical fiber with the reported peak absorption wavelength [47] of the complex in an aqueous solution is caused by the error of instrument wavelength calibration. The UV/Vis absorption spectrum of the complex in an aqueous solution recorded with our optical fiber compatible spectrometer is shown in Fig.…”

“…The resulting complex has a peak absorption around 560 nm and this complexation reaction has been used in traditional UV/Vis absorption spectrometry for the determination of copper ions in water through the addition of excess ammonia into the sample solution [47].…”