Citric acid, barium salt

Firstly, the calcium and barium salts of organic acid are frequently used in the preparation of the acids themselves, by treatmont with mineral acids such as sulphuric, hydrochloric or phosphoric. This method was first utilised by the Swedish chemist, Sclieele (about 1770), who discovered by this means tartaric, citric, malic and oxalic acids. 

Ba Srj TiOj is synthesized, barium and strontium carbonates or acetates are dissolved in the aqueous solution containing water-soluble titanium complex. Although strontium salts can be dissolved in water relatively easily (there are numerous water-soluble strontium salts), strontium forms precipitate with citric acid that is hardly soluble in water. Therefore to utilize citratoperoxotitanium complex for the synthesis of Ba Srj. Ti03 is difhcult. In such a case, the com-plexing agent should be changed. 

Barite BaS04 Na2C03, Na2Si03 AICI3, FeCb, Barium salt, lead salt R-710, 765, 825, 830, 840,845, oil acids and sulfates Alcohols, pine oil, cresylic add Aerosol surfactant Na2Si03, citric acid... 

Barium chloride Barium salts, aqueous Carbonic acid Castor oil Chlophen A 60 Chloral hydrate, aqueous Chloramine, aqueous Chloride of lime, aqueous Chlorine, wet + dry Chloroacetic acid Chlorobenzene Chloroform Chloromethyl o-Chloronaphthalene Chloroprene Chlorosulfonic acid Chromic acid Citric acid... 

The periodic acid method cannot be applied directly to the determination of DBA in the 5% citric extractant due to the fact that citric acid itself reacts with periodic acid and interferes in the analysis. It is, therefore, necessary to devise a method for removing citric acid from this extractant prior to the determination of DBA. By adding a slight excess of barium carbonate to the extractant, citrate ions are precipitated as barium citrate, and the insoluble salt then removed from the solution by centrifuging. However, it was found that the clear aqueous phase recovered by this procedure still contained sufficient citrate ions to interfere in the periodic acid method (due, presumably, to the presence of dissolved barium citrate, which is slightly soluble in water). To remove the last trace of barium citrate from the extractant, it was passed down a column of Amberlite IRA-400 ion exchange resin (in the chloride form). 

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