A little remained of the experiments conducted previously.
The first step is to define a proof of concept. Previous research has demonstrated that silver ion forms insoluble solids of bromide (AgBr) and can remove these halide ions from water. The first part of our proof of concept was the use of photo reduction method to produced reduce silver nanoparticles. Confirmation of the reduction of silver was qualitatively obtained by the formation of a brown precipitate. In the second part of this proof of concept, silver nanoparticles were reused in a new water batch containing bromide. The color change from brown to yellow indicated full cycle regeneration.
So, we decided to conduct the same experiment several times. The idea is to make sure we get the same results multi times. Here are some tables to show the results.
| Silver bromide
First round of experiments completing the cycle in the recycling of silver |
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A B C
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| Precipitate made from
AgNo3 + NaBr. |
Vacuumed washed with ultra-pure water.
Sonicated /Irradiated at intervals of 10 and 30 min respectably. |
Irradiated precipitate was added to a NaBr solution while sonicating for 10 min.
A) 10 min centrifuged and B) 60 min centrifuged there are no difference. C) Dried overnight
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| Silver bromide
Second round of experiments completing the cycle in the recycling of silver |
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| Vacuumed washed with ultra-pure water.
Sonicated /Irradiated at intervals of 10 and 30 min respectably.
|
Irradiated precipitate was added to a NaBr solution while sonicating.
Centrifuge for 60 min. Dried overnight. |
Vacuumed washed with ultra-pure water.
Sonicated /Irradiated intervals of 10 and 30 min respectably. |
| Silver bromide
Third round of experiments completing the cycle in the recycling of silver |
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 |
 |
 |
| Irradiated precipitate was added to a NaBr solution while sonicating.
Centrifuge for 60 min. Dried overnight. |
Vacuumed washed with ultra-pure water.
Sonicated /Irradiated at intervals of 10 and 30 min respectably. |
Irradiated precipitate was added to a NaBr solution while sonicating.
Centrifuge for 60 min. |
| Silver bromide
View of the different stages of the experiment |
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| A B C
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Appreciation of the difference in color.
A) Precipitate from original solution. B) Precipitate Irradiated for the first time. C) Fourth time precipitate added to NaBr solution. |
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After drying out the brown precipitate on our final round, we compared it with the original precipitate. The color change from pale-yellow to brown after irradiation and back to dark-yellow on the fourth round indicates full cycle regeneration of silver. Confirming our proof of concept.
After completing the proof of concept, there could be a full research investigation, to include both quantitative and qualitative components. Another method to use can be silver carbonate solution for its effectiveness in the bromide ion removal.