Funnel method

Metallic Powders - Determination of Apparent Density ISO 3923 Part 3 Oscillating Funnel Method (Fig. 31)... 

Metallic powders—determination of apparent density, ISO 3923 Part 1 Funnel method. 

The theoretical basis of the chromatographic approach is fundamentally the same as for a separatory funnel method as described in the text—a phase boundary between a polar phase and a nonpolar phase. Octanol (nonpolar) can be used as a mobile phase with a polar stationary phase. A second option is to use a nonpolar stationary phase such as C18 (octadecylsilane) with an aqueous mobile phase. The researchers employed a gradient elution technique in which the composition of the mobile phase changed during the course of the analytical run from primarily... 

ISO 3923-1 (1979) Apparent Density Funnel Method. International Organisation for Standardisation, Geneva. ISO 3923-2 (1981) Scott Volumeter. International Organisation for Standardisation, Geneva. 

In order to dry the crystals, the Buchner funnel is inverted over two or three thicknesses of drying paper (i.e., coarse-grained, smooth surfaced Alter paper) resting upon a pad of newspaper, and the crystalline cake is removed with the aid of a clean spatula several sheets of drying paper are placed on top and the crystals are pressed flrmly. If the sheets become too soiled by the mother liquor absorbed, the crystals should be transferred to fresh paper. The disadvantage of this method of rapid drying is that the recrystallised product is liable to become contaminated with the Alter paper flbre. 

Method 2 (from concentrated sulphuric acid and concentrated hydrochloric acid). The apparatus is shown in Fig. II, 48, 1. The upper funnel has a capacity of 100 ml. and the lower one of 500 ml. A capillary... 

Method 2 (from potassium bromide and sulphuric acid). Potassium bromide (240 g.) is dissolved in water (400 ml.) in a litre flask, and the latter is cooled in ice or in a bath of cold water. Concentrated sulphuric acid (180 ml.) is then slowly added. Care must be taken that the temperature does not rise above 75° otherwise a little bromine may be formed. The solution is cooled to room temperature and the potassium bisulphate, which has separated, is removed by flltration through a hardened Alter paper in a Buchner funnel or through a sintered glass funnel. The flltrate is distilled from a litre distilling flask, and the fraction b.p. 124 127° is collected this contains traces of sulphate. Pure constant boiling point hydrobromic acid is obtained by redistillation from a little barium bromide. The yield is about 285 g. or 85 per cent, of the theoretical. 

Sulphuric acid method. Place 20 g. of commercial cycZohexanol and 0-6 ml. of concentrated sulphuric acid in a 150 or 200 ml. round-bottomed or bolt head flask, add 2-3 chips of porous porcelain, and mix well. Fit the flask with a fractionating column, a Liebig condenser, adapter and filter flask receiver as in Section 111,10 (1). Heat the flask in an air bath (Fig. II, 5, 3) at such a rate that the temperature at the top of the column does not rise above 90° alternatively, an oil bath, heated to a temperature of 130-140°, may be used. Stop the distillation when only a small residue remains and the odour of sulphur dioxide is apparent. Transfer the distillate to a small separatory funnel. 

Method A. In a 500 ml. round-bottomed flask, fitted with a reflux condenser attached to a gas trap (Fig. II, 13, 8), place 59 g. of succinic acid and 117-5 g. (107-5 ml.) of redistilled acetyl chloride. Reflux the mixture gently upon a water bath until all the acid dissolves (1-2 hours). Allow the solution to cool undisturbed and finally cool in ice. Collect the succinic anhydride, which separates in beautiful crystals, on a Buchner or sintered glass funnel, wash it with two 40 ml. portions of anhydrous ether, and dry in a vacuum desiccator. The yield of succinic anhydride, m.p. 118-119°, is 47 g. 

Method A. Pit a 1-litre three-necked flask with a mercurj -sealed stirrer, a reflux condenser, and a dropping funnel. Place 57 g. (73-5 ml.) of dry /cr<.-butyl alcohol (1), 101 g, (106 ml.) of A.R. dimethylaniline and 100 ml. of anhydrous ether in the flask, set the stirrer in motion, and... 

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