Barium chloride to remove sulfate ions
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This post was last edited by sunjl1981 on 2013-1-6 21:07. What is the main purpose of adding hydrochloric acid to adjust the pH value in the process of removing sulfate ions from ion-exchange membrane caustic using the barium chloride method? Please discuss it. # hcbbs
In my opinion, adjusting the pH value is primarily aimed at controlling the amount of chloride ions; from the perspective of ionic balance in salt solutions, this is done to ensure that chloride ions react as much as possible with barium ions.
It is indeed present on the standard flowchart, but we do not add acid to adjust the pH value in our current production process, and the performance is still good. Could this be considered a waste? We add alkali to make adjustments earlier on, then acid to make adjustments later, and again alkali after salt treatment to adjust the alkalinity level.
Hydrochloric acid is added to neutralize excess hydroxide ions; if there are too many hydroxide ions, they will react with barium chloride to form barium hydroxide, resulting in a waste of barium chloride. Therefore, adding acid is quite cost-effective.
I heard that after Haohua Aerospace improves the chlorination process, it is no longer necessary to use sodium hydride, nor is any alkali required. The pH of the brackish water after chlorination is between 1.0 and 1.5, so there is no need to add hydrochloric acid to adjust the pH.