Use of Thermochromatography for Rapid Chemical Separations

Abstract

The deposition temperatures of elemental states and/or chemical compounds of the elements Na, Co, Zn, Ge, As, Br, Rb, Ag, Cd, In, Sn, Sb, Te, I, Cs, and Ba have been determined. In the majority of cases the material on which the deposition takes place has been quartz, but some data for other materials have also been obtained.high temperature (about 800 °C) by means of a heating element in order to prevent the deposition of other compounds than those of very high deposition temperature in this part of the apparatus. Precautions are also taken to minimize backward diffusion of the sample to regions of low temperature. ZusammenfassungDie Ablagerungstemperaturen der Elemente Na, Co, Zn, Ge, As, Br, Rb, Ag, Cd, In, Sn, Sb, Te, J, Cs und Ba in elementarer Form bzw. als chemische Verbindungen sind bestimmt worden. In den meisten Fällen fand die Ablagerung auf Quartz statt; es wurden jedoch auch einige Daten für andere Materialien ermittelt. RésuméOn a déterminé les températures de déposition des états élémentaires et/ou des composés chimiques des éléments Na, Co, Zn, Ge, As, Br, Rb, Ag,Cd, In, Sn, Sb, Te, I, Cs, et Ba. Dans la plupart des cas le matériel de déposition fut le quartz; cependant, des informations ont été obtenues aussi pour les autres matériels.

Chemistry of Superheavy Elements

“…[156,157] This technique has the potential for very fast separations in the millisecond region, possibly giving access to short-lived nuclides of elements beyond Z = 114.…”

Vacuum-Thermochromatography of Carrier-free Species

“…(5) and (7) into (8), this integral has the Solution (for T = Ta, i. e. the adsorption temperature Tj of the volatile species in the chromatographic tube [10]): Under the assumption of mobile adsorpiion of an ideal gas in an empty tube the corrected partition coefficient ki is given by [10] with Ef (jc) = integralexponential function of x [12].…”

“…RUD-STAM et al [4,5] applied thermochromatographic techniques at the collector side of a mass Separator in order to obtain chemical separations of the Clements within an isobaric chain. This method was shown to be very useful for studies of short-lived isotopes of the halogens, of zinc and cadmium [6].…”

The Thermochromatography of Metallic Elements in Titanium Columns

“…By varying the temperature range, the stationary and mobile phase, thermochromatography is applicable to almost all of the elements of the periodic table [1,2]. Numerous papers are devoted to volatile compounds, but only a few to the thermochromatography of elements [2][3][4][5][6][7], We believe that it may be advantageous to separate trace amounts in the elemental state in metallic columns, because different types and energetics of bonding between metallic surfaces and adatoms could provide separation factors exceeding those attainable by distillation and sublimation of macroamounts [8,9]. Theoretical calculations of the enthalpy of adsorption (A// ad ) on metallic surfaces from first principles are mostly incorrect (refs.…”