Sodium gallate

Electrolysis. GalHum can be extracted by direct electrolysis of the aluminate solution at a strongly agitated mercury cathode. The recovery from a sodium gallate solution resulting from the carbonation process is another possibiHty. This process is probably no longer operative because of the environmental problems associated with the mercury. 

Purification. Extraction from aluminum or 2inc ores produces cmde galHum metal or concentrates. These concentrates are transformed to sodium gallate, galHum chloride, or galHum sulfate solutions which are purified, then electroly2ed. GalHum is deposited as a Hquid. 

The gallium analogue of zeolite A can be prepared starting from sodium gallate, NaGa02 (instead of sodium aluminate) and sodium silicate. The reaction would be undertaken hydrothermally in a sealed reaction vessel ... 

Of these, the P- and P"-aluminas have been studied most extensively. The isostructural sodium gallates, potassium, rubidium and cesium gallates, aluminates, and ferrites are also known. The ideal formulas for the p and P" structures are AMuOn and A2M11O17, respectively, but all of the compounds are intrinsically nonstoichiometric and the actual alkali content is always greater than unity but less than 2. The most obvious charge compensation mechanism is alower-valence cation substitution for trivalent M , namely Ai, )Oi7 (M = Mg, Co, Ni, Zn) and... 

Al + x(Mj jt. 2 Li 2)Oi7- Without these dopants, the ferrites are charge-compensated by Fe (giving rise to electronic conductivity), and sodium gallates, by sodium substitution for gallium. For aluminates, these variants are impossible. As a result. 

The compound GaO(OH), with a diaspore structure, is obtained in slow precipitation of a sodium gallate solution by atmospheric COg, according to Bbhm and Kahan. 

C12 to C20, primarily Ci6 to ( is), used as surface lubricants in the manufacture of food-contact articles. The method, which uses ethyl palmitate (Eastman Chemicals No. 1575 Red Label) as an internal standard, has been validated at 200 ppm total FAME [185]. Other FAME standards (methyl palmitate, methyl stearate, methyl oleate, methyl linoleate and methyl linolenate) are available (Applied Science Laboratories) [116], Worked out examples of additive determinations are given in the Food Additives Analytical Manual [116], which also describes a great many of indirect food additives, such as BHA, BHT, TBHQ, l-chloro-2-propanol, DLTDP, fatty acid methyl esters, w-heptyl-p-hydroxybenzoate, propyl-gallate, sodium benzoate, sodium stearoyl-2-lactylate, sorbitol and phenolic antioxidants. EPA methods 606 and 8060 describe the CGC separation of phthalate esters (direct injection) (cf. Figure 4.2). 

Annex III lays down the conditions of use for permitted preservatives and antioxidants, with lists of foods and maximum levels in each case. Part A lists the sorbates, benzoates and p-hydroxybenzoates, E 200-E 219 part B lists sulphur dioxide and the sulphites, E 220-E 228 part C lists other preservatives with their uses, including nisin, dimethyl dicarbonate and substances allowed for surface treatment of certain fruits, E 249 potassium nitrite, E 250 sodium nitrite, E 251 sodium nitrate and E 252 potassium nitrate, E 280-E 283 propionic acid and the propionates part D lists the antioxidants E 320 butylated hydroxyanisole (BHA), E 321 butylated hydroxytoluene (BHT), E 310 propyl gallate, E 311 octyl gallate, E 312 dodecyl gallate, E 315 eiythorbic acid and E 316 sodium erythorbate. 

Sodium bisulfite Propyl gallate Citric acid... 

From 2 to 3 c.c. of the ink are diluted with 5-6 vols. of water and treated with excess of 20% sodium acetate solution, which precipitates the iron tannate but leaves the gallate in solution. After some time the liquid is filtered and the precipitate washed on the filter with the same sodium acetate solution until the liquid passes through the filter colourless. 

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