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ASTM D1394-76(R2020) pdf free download

ASTM D1394-76(R2020) pdf free download.Standard Test Methods for Chemical Analysis of White Titanium Pigments
6. Procedure
6.1 Place about 0.5 g of the sample in a 250-mL glass beaker, 4 and add 20 mL of H 2 SO 4 (sp gr 1.84) and 7 to 8 g of (NH 4 ) 2 SO 4 . Mix well and boil for a few minutes. The sample should go completely into solution; a residue denotes the presence of silicon dioxide (SiO 2 ) or siliceous matter. Cool the solution, dilute with 100 mL ofwater, heat to boiling, let settle, filter, wash with hot H 2 SO 4 (1+19) until free of titanium, and test the residue for lead, etc. 6.2 Test the filtrate for calcium, zinc, iron, chromium, etc., by the regular methods of qualitative analysis. 5 For the iron determination add to a portion ofthe filtrate 5 g oftartaric acid, render slightly ammoniacal, pass in H 2 S in excess, and digest on a steam bath. No precipitate after 30 min indicates the absence of iron, nickel, cobalt, lead, copper, etc. A black precipitate readily soluble in dilute HCl denotes iron. For titanium, test a small portion of the original filtrate with H 2 O 2 (a clear yellow-orange color should result) and another portion with metallic tin or zinc (a pale blue to violet coloration should result). Negative results should be shown for sulfide, carbonate, or appreciable water-soluble matter.
9. Apparatus
9.1 Jones Reductor 6 having a zinc column at least 450 mm in length, and 19 mm in diameter (Fig. 1 and Fig. 2). The filtering pad must be tight enough to hold all the particles of amalgamated zinc resting on it, and may be made of asbestos or, preferably, glass-wool supported by platinum gauze or a perforated porcelain plate. Use the least amount (0.1 to 1.0 %) of mercury that will enable satisfactory control of hydrogen evolution, since heavy amalgamation tends to reduce the rate of reaction. Prepare the amalgam by washing 20-mesh zinc for 1 min in enough 1 NHCl to cover it, adding the proper amount of 0.25 M mercuric nitrate or chloride solution, and stirring rapidly for 3 min. Decant the solution and wash the amalgam with water and store under water to which a few drops of HCl have been added. After using, keep the reductor filled with water when not in use, in order that basic salts will not be formed and clog it.
11. Procedure
11.1 Determine the dry weight of a weighing bottle and cap to 0.1 mg. Weight to 0.1 mg 300 to 350 mg of the sample to be analyzed into the weighing bottle. 11.2 Dry the specimen in the opened weighing bottle for 2 h at 105 to 110°C. Cool in a desiccator, cap the bottle, and weigh as rapidly as possible. Calculate the dry weight of the specimen and use in the actual calculation. 11.3 Transfer the dried specimen to a dry 250 mL chemical- and heat-resistant glass beaker, 4 add 20 mL of H 2 SO 4 (sp gr 1.84) and 7 to 8 g of (NH 4 ) 2 SO 4 . Mix well and heat on a hot plate until dense white fumes are evolved, and then continue the heating over a strong flame until solution is complete (usually requires not over 5 min ofboiling) or it is apparent that the residue is composed of SiO 2 or siliceous matter. Caution should be observed in visually examining this hot solution. Cool the solution, dilute with 100 mL of water, stir, heat carefully to boiling while stirring, let settle, filter through paper, and transfer the precipitate completely to the paper. 11.4 Wash the insoluble residue with cold H 2 SO 4 (1+19) until titanium is removed. Dilute the filtrate to 200 mL and add about 5 mL ofNH 4 OH to lower the acidity to approximately 10 to 15 % H 2 SO 4 (by volume). Wash out the Jones reductor with H 2 SO 4 (1+19) and water, leaving sufficient water in the reductor to fill to the upper level of the zinc. (These washings should require not more than one or two drops of0.1 NKMnO 4 solution to obtain a pink color.) Empty the receiver, and put in it 25 mL of ferric sulfate solution. Reduce the prepared titanium solution as follows: 11.4.1 Run 50 mL of H 2 SO 4 (1+19) through the reductor at such a uniform rate as to require 5 to 10 min for passage. 11.4.2 Follow this with the titanium solution at such a uniform rate as to require 10 min to pass through the reductor. 11.4.3 Wash out with 100 mL of H 2 SO 4 (1+19). 11.4.4 Finally run through about 100 mL ofwater.

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