Gas wash

Extra coarse 170-220 Filtration of very coarse materials. Gas dispersion, gas washing, and extractor beds. Support of other filter materials. 

In addition to the color and the tinctorial strength, which ate very important factors for the molecular design of anthraquinone dyes, affinity for fibers, various kinds of fastness (light, wet, sublimation, nitrogen oxides (NO ) gas, washing, etc), and apphcation properties (sensitivity for dyeing temperature, pH, etc) must be considered thoroughly as well. 

It is advisable to insert a safety bottle to avoid any run-back of sulfuric acid into the reaction flask. The gas washing bottle must be cooled by immersion in a large water bath (15°) the sulfuric acid solution is replaced by a fresh 5N solution when neutralized by evolved ammonia (checked by phenolphthalein). 

Submitters used nitrogen purified by passing it through a set of gas wash bottles containing Fieser s solution, concentrated sulfuric acid, sodium hydroxide, and calcium chloride. 

Samples are hydrolyzed with hydrochloric acid and stannous chloride solution at elevated temperature, and the evolved carbon disulfide is drawn with an air steam through two gas washing tubes in series containing lead acetate and sodium hydroxide solutions and an absorption tube containing an ethanolic solution of cupric acetate and diethanolamine. Lead acetate and sodium hydroxide remove hydrogen sulfide and other impurities. In the absorption tube, the carbon disulfide forms two cupric complexes of Af,Af-bis(2-hydroxyethyl)dithiocarbamic acid with molecular ratios Cu CS2 of 1 1 and 1 2. These complexes are measured simultaneously by spectrophotometry at 453 nm. 

Hemispherical, temperature-regulated, heating mantle, 500-W, Horst or equivalent Gas washing tubes, in glass, 250-mL (Pyrex), equipped with spherical socket joints Trapping (absorption) tube, in glass, 250-mL (Pyrex), equipped with spherical socket joints... 

Figure 1 Apparatus for hot acid decomposition of aUsylenebis(dithiocarbamates) and distillation of carbon disulfide. 1 = Three-necked round-bottom flask 2 = air inlet tube 3 = dropping funnel 4 = Liebig reflux condenser 5 = gas washing tubes 6 = carbon disulfide absorption tube.

Commercial hydrogen sulfide is passed through a (reversed) empty 500-ml. Drechsel gas-washing bottle and then through 250 ml. of deaerated water in a similar bottle (not reversed). 

The checkers found that best results were obtained when the slowest detectable nitrogen flow was used with a fairly rapid ethylene flow (about 1 in. of foam in the gas washing bottle at the reaction temperature). 

Carry out the ozonisation in a thin-walled gas wash-bottle (capacity 400 c.c.) with an inlet tube widened out to a bell shaped opening or twisted to a spiral. Connect the bottle to the ozoniser by bending the inlet tube of the former at a right angle so that it can be inserted into the delivery tube of the ozoniser, which is fitted with a mercury seal. 

SO2 content of the gas was determined by sparging into a 125 ml gas washing bottle containing a known amount of I2 in acetate buffer at pH A-5.5 with a starch indicator. N2 flow was measured by a wet test meter. 

The hygroscopicity of a propellant is detd rapidly in an apparatus consisting of 2 identical gas washing bottles provided with fritted glass plates near the bottom. The outlets at the bottom are connected through a diaphragm pump... 

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