Formation of Palladium(II) Hydroxychloride Complexes and Precipitates in Sodium Chloride Solutions and Seawater

Authors

Robert H. Byrne, University of South FloridaFollow
Wensheng Yao, University of South Florida

Document Type

Article

Publication Date

2000

Digital Object Identifier (DOI)

https://doi.org/10.1016/S0016-7037(00)00501-9

Abstract

Spectrophotometric measurements of Pd(II) in 0.5 M NaCl indicate that the PdCl₃OH²⁻ formation constant at 25°C is _ClK^∗₁ = [PdCl₃OH²⁻][H⁺][Cl⁻][PdCl₄²⁻]⁻¹ = 10^−8.98. This constant is more than two orders of magnitude smaller than previous results derived through solubility analysis. Kinetic experiments indicate that equilibration between PdCl₄²⁻ and PdCl₃OH²⁻ is complete in less than one second. The discrepancy between depictions of Pd(II) speciation obtained by using spectrophotometric and solubility analysis is apparently caused by the formation of mixed hydroxychloride solid phases (PdCl_aOH_2−a), rather than pure Pd(OH)₂(s), when Pd(OH)₂(s) is equilibrated in concentrated chloride solutions at high pH. In Pd(II) solubility analysis, and solubility analyses of other strongly hydrolyzed metals in seawater, the composition of the solid phase must be carefully examined for appropriate deconvolution of data.

Was this content written or created while at USF?

Yes

Citation / Publisher Attribution

Geochimica et Cosmochimica Acta, v. 64, issue 24, p. 4153-4156

Scholar Commons Citation

Byrne, Robert H. and Yao, Wensheng, "Formation of Palladium(II) Hydroxychloride Complexes and Precipitates in Sodium Chloride Solutions and Seawater" (2000). Marine Science Faculty Publications. 1728.
https://digitalcommons.usf.edu/msc_facpub/1728