Methods for removing iron, arsenic, and heavy metal elements from sulfuric acid solutions obtained by ammonia-based desulfurization
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Our company aims to remove iron, arsenic, and heavy metal elements from the sulfuric acid an solution produced by ammonia-based desulfurization, and to further process the substandard or standard sulfuric acid an products resulting from this process into high-quality sulfuric acid an. I don’t know what method would be better! I would appreciate it if fellow sailors could help offer some suggestions; thank you all in advance. reward_7ree
Iron is removed by hydrolysis; after adding more ammonia, the pH is adjusted to a certain value, which causes the iron to precipitate out. It is then filtered off, and pH calculations and experiments are carried out.
What about the other elements? When the pH value is too high, it affects the formation of sulfuric acid an crystals.
I’m not sure about that. Let’s first run some small experiments to see what the results are; what I say might not be correct
What is the concentration of sulfuric acid An? What are the concentrations of heavy metal ions such as iron?
If the concentration of heavy metal ions is below 100 ppm, ion exchange resins can be considered; however, removing arsenic proves to be more complicated. I’m not aware of the specifics of your liquid mixture, so it’s uncertain whether arsenic removal resins will be effective in this case. Please contact Li at 18969098391 for details.
The specific ion concentrations will need to be determined through a full analysis of the sulfuric acid AN solution in the next step. Do you mean that 100 ppm refers to the highest conditions using ion exchange resin? After resin exchange, the heavy metal elements are removed; but could other trace elements remain, and would that have an impact on the final crystals of sulfuric acid an? At present, this is just a proposal; many tests will still be needed when it is put into practice. Are you in this industry?
We are a professional manufacturer of ion exchange resins, Zhenguang Resins. I suppose the concentration of these heavy metal ions in the solution you’re talking about isn’t high; they can generally be removed using resins. If it is not possible to introduce other ions, ammonium-type resins can be used to replace the heavy metal ions; the ions that are released are ammonium ions, so no other impurity ions will be introduced. As for arsenic removal, it’s more complicated – it depends on the conditions of your liquid material. Moreover, the price of arsenic removal resins is extremely high; I’m not sure if you can accept that cost. Foreign estimates suggest it needs over 200,000 per ton. Our company has it too, but I’m not quite sure about the specific price. It will probably cost over 100,000 as well. In short, the problem you mentioned should be solvable using ion-exchange resins.
If the iron ion concentration is very high, above 100 ppm, it is likely to cause problems. Due to the special properties of iron ions, certain specialized resins can be used to remove them, but elution is difficult; relevant experiments are needed to determine which resin is most suitable for this purpose. At present, strong acid cation resins and chelating resins are not suitable, as it is difficult to elute iron ions from these resins after they have absorbed them. In other words, it can only be used once, or its lifespan is relatively short. You can contact me if needed.
Trace amounts of iron ions can be removed using extraction.