1. Brintplasmareduktion
Status efter 10 år

2. • Plasmabehandlingens virkemåde og
forventningerne til metoden
• Reaktivitet af plasmabehandlet materiale
• Udvaskning af klorider fra arkæologisk
jern
• Bestemmelse af behandlingens slutpunkt
• Metodens perspektiver
• Et spændende nybrud

7. β-FeOOH,xHCl,yH2O

10. kloridudvaskning
Forhindre korrosion under processen
• Hindre iltadgang
• Passivere med base eller inhibitor
Sikre adgang til alle klorider
• Omdanne til ikke klorholdige korrosionsprodukter f.eks.
αFeOOH, Fe3O4, eller Fe2O3
Sikre udvaskningshastigheden
• Øge porøsiteten ved omdannelse af korrosionsprodukter
• Undgå udfældning af hydroxyder

17. Metodens perspektiver

18. A fast and non-destructive
method to document and quantify
the efficiency of metals
conservation
Henning Matthiesen & Karen StemannPetersen, National Museum of Denmark

19. Oxygen Consumption
Concept: the decrease in
oxygen concentration is
measured in an enclosed
air volume around the
artifact
Assumption: a high
oxygen consumption
indicates an unstable
object
xMe + yO2 → MexO2y
Can this be used during
daily conservation work?

20. Optical oxygen measurements
Transparent container wall
Light
transmitted to
sensor
Oxygen sensor
inside container
ptic
o
re
Fib be
pro
Adhesive
Light received
from sensor

21. Small air volume: faster decrease in oxygen concentration
𝑂𝑥𝑦𝑔𝑒� 𝑐𝑜�𝑠𝑢𝑚𝑝𝑡𝑖𝑜� 𝑟𝑎𝑡𝑒 ሾ𝑔Τ 𝑑𝑎𝑦ሾ=
�𝐼𝑁𝐼� × � × d�/d𝑡
100

23. Determination of air volume in bag
𝑂𝑥𝑦𝑔𝑒� 𝑐𝑜�𝑠𝑢𝑚𝑝𝑡𝑖𝑜� 𝑟𝑎𝑡𝑒 ሾ𝑔Τ 𝑑𝑎𝑦ሾ=
�𝐼𝑁𝐼� × � × d�/d𝑡
100
A known volume of air or nitrogen
is introduced in the bag
The air volume is calculated from
the reative change in oxygen
saturation
The volume is determined with an
accuracy of approx 10%
Example: 20 mL of air is introduced after 3 days

24. 120
Rivet plate, wrought iron
100
80
)
t
a
s
%
(
n
e
g
y
x
O
60
untreated
untreated
untreated
annealed
annealed
wax coated
40
20
0
0
0.2
0.4
0.6
Time (days)
0.8
1