chemical physics of discharges - Argonne National Laboratory

- Tracer
Fe59
Fe59
' ~e75
se75
,8875
se75
218
Table I1
Recovery of Trace Elements from Ashed Filter Paper
~. Highest Percent in
Max. sample Percent Oxidation Highest
Compound Temperature Recovered State Oxidation State
I
123
I11
95
120
I11
100
110
250
ll0
250
ll0
250
120,
150
* Recovered after rinsing tube with HF-HN03
V
V
V
V
I
I
VI11
.VI11
The behavior of silver ion represents a different type of ashing loss. As
opposed to the other metals in this study, only 75 to 90 per cent of the Agum could
be recovered from the borosilicate sample holder by rinsing with dilute nitric acid.
To recover the remainder of the Ague? the glassware had to be repeatedly rinsed with
a warn mixture of nitric and hydrofluoric acids. gY maintaining the system at low
temperature this difficulty was ameliorated, but not eliminated.
Conclusion: A number of active species are known to be present in the luminous
electrodeless discharge. Although a sikilarity between reactions in the plasma and
those of discharged oxygen is,noted, it cannot be concluded that within the plasma
onlythe reactions of atomic owgen are significant. The present study indicates
appropriate conditions for the application of the electrodeless discharge to decompose
carbonaceous materials prior to elemental analysis. Specifically, increasing sample
temperature to 200-300OC leads to an improvement in ash- rate without appreciably
increasing volatility losses.
91
93
100
100
--
c
-
-
--
l
Acknowledgement //
, The electrical apparatus used in this study was constructed by James Breitmsier.
The assistance of Juan Wong and Daniel Silvers is appreciated. Walter Holland, Harvey
Beaudry and Robert Reinhart assisted in preliminary studies performed under a contract
between Union Carbide Chemical Corporation and the Laboratorg for Electronics.
stw was supported by grants from the North Carolina Engineering Foundation and North
C a r o b State University Professional Development Fund.
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