Distillation equipment steam

Neutralise the cold contents of the flask with 500-600 ml. of 40 per cent, aqueous sodium hydroxide solution, equip the flask for steam distillation and steam distil until about 1 litre of distillate is collected. The steam distillate separates into two layers. Add solid sodium hydroxide (< 100 g.) to complete the separation of the two layers as far as possible. Remove the upper (organic) layer and extract the aqueous layer with three 50 ml. portions of chloroform. Dry the combined organic layer and chloroform extracts with anhydrous potassium carbonate and distil the mixture through a short fractionating column (e.g., an 8 Dufton column) after a fore run of chloroform, followed by pyridine, collect the crude 4-ethylpyridine at 150-166° (49 g.). Redistil through a Fenske-... 

The aqueous acid solution is transferred to a i-l. round-bottomed flask provided with a separatory funnel and equipped for steam distillation. A solution of 125 g. of sodium hydroxide in 250 cc. of water is added through the funnel, and the mixture is distilled with steam (Note 4). The first liter of distillate contains most of the amine, but the distillate should be collected until it is only faintly alkaline. A small residue containing di-(a-phenylethyl)-amine and neutral substances remains in the flask and may be discarded. 

This is the basis for a common method for the determination of ammonia in soil.1 Soil is suspended in water and placed in a Kjeldahl flask. The suspension is made basic by the addition of a strong (5-50%) sodium hydroxide solution, and the flask is immediately attached to a steam distillation setup. Steam distillation of the suspension carries the released ammonia to an Erlenmeyer flask, catching the distillate in a standardized acid solution that is subsequently back titrated via acid-base titration. The amount of ammonia in soil can be calculated from the end point of the titration. This procedure is similar to a standard Kjeldahl determination and can be carried out using the same equipment, although no digestion is needed. 

Phenylethyl Ketone. 200 g of finely powdered anhydrous aluminum chloride is suspended in 300 g of dry benzene in a flask that is cooled and equipped with a good stirring device. A mixture of 126 g of propionyl chloride and 105 g of benzene is added dropwise, with stirring, over 3 hours. After the 3 hours, the reaction mixture temp is kept at 50°. The contents of the flask are cooled and poured over crushed ice. Add 50 cc of coned HCl acid and remove the phenylethyl ketone and benzene by distillation with steam at 200-220° to yield 152 g of the ketone. 

Preparation of Picric Acid (Catalytic Process). Two hundred grams of benzene in a 2-liter round-bottom flask equipped with a sealed-on condenser is refluxed on the sand bath for 7 hours with 600 cc. of nitric acid (d. 1.42) in which 10 grams of mercuric nitrate has been dissolved. The material is then transferred to another flask and distilled with steam. Benzene comes over, then nitrobenzene, then finally and slowly a mixture of dinitrobenzene and dinitrophenol. The distillation is continued until all volatile matter has been removed. The liquid in the flask is filtered hot and allowed to crystallize. If the picric acid is not sufficiently pure, it is recrystallized from hot water. 

Electrolyte container. 2 — Cells, J — Catholyte container, 4 — Anolyte (persulphnrlo acid) container, 5 — Lead distillation coil, 6 — Heating steam inlet, 7 — Tank tor steam condensate, S — Separator of liquid from vapour, 9 — Auxiliary distillation equipment, 10 — Main column for fractional condensation, 11 — Second column, 12 — Barometric oondenser, 13 — Vacuum pump, 14 — Acid dilution vessel. 13 — Acid purifier. 

Uncondcnsed vapour from the first tower is led to the bottom part of the second column which is scrubbed with the condensate obtained from the heating steam which condenses in the distillation equipment. The remaining vapour then leaves the second column and is led to a barometric condenser of standard design connected to a vacuum pump, which maintains a reduced pressure of 110 to 140 mm Hg in the whole distillation equipment and 40 to 60 mm Hg in the condensation. The distillation yield reaches 90 to 92 per cent. A flow sheet is shown in Fig. 140. 

Fie. 40. Vacuum distillation equipment for substances which solidify easily (napnthols, phenylenediamine, etc.). The apparatus for large quantities (1000-30(X) kg.) is equipped with a stirring mechanism to prevent charrine. 1, distillation vessel 2, receiver with steam or water jacket 3, steam heated times to prevent solidification 4, trap to collect water and sublimate 5, line to pump. 

A 3-1. three-neck flask is equipped with a stirrer, a dropping funnel, and a wide-bore distillation head with attached air condenser and distillation receiver. Bromine (800 g., 5.0 moles) is added to 1155 g. (10.0 moles) of pyridine hydrochloride in the flask over a period of 5 minutes with stirring. Hood.) The flask is heated to 160-170° for 1 hour and then to 195-200° for another hour as evolution of hydrogen chloride ceases. The system is evacuated with a water pump, and a manometer is connected to the flask in place of the dropping funnel. The distillation receiver is cooled with running water. 3,5-Dibromopyridine distils over, followed by 3-bromopyridine hydrobromide as the bath temperature is raised to 220° and the pressure drops to about 25 mm. The combined solid distillate is treated with a solution of 200 g. of sodium hydroxide in 1 1. of water, the mixture is extracted with benzene, and the benzene solution is distilled. There is obtained 300 g. (37%) of 3-bromopyridine boiling at 61-63°/15 mm. The residue from the above operation is distilled with steam to give in the distillate 144 g. (26%) of 3,5-dibromopyridine, m.p. 110-111°. 

The steam required for a steam distillation can be provided by an external source, such as piped steam in the laboratory or steam generated by heating water in a flask, which is then piped into the distilling flask. Steam is very dangerous and the safest way to generate steam is to heat the compound with a vast excess of water in the distilUng flask steam is generated in situ. The equipment for steam distillation is illustrated in Fig. 15.9 and the procedure is described in Box 15.5. 

Combustible vapors allowed to mix with air may ignite violently. Prevention of these incidents is mostly obvious however, undetected corrosion has sometimes led to vapor release with violent gas explosions. Vacuum distillation equipment must be protected against air intrusion, for example in case of steam supply failure. 

Perform Installation Qualification of deionizer and distillation equipment, holding tanks, clean steam generator, and distribution system. 

Because of its low purchase price and a calorific value equivalent to kerosine, which makes used white spirit useful as a cement kiln fuel, very little white spirit is recovered. If recovery is attempted its high boiling point makes atmospheric pressure distillation liable to lead to a cracked odour in the distillate. Vacuum distillation or steam distillation does not have this drawback but the latter is costly in steam and the former needs vacuum equipment. 

After fermentation, the wort (agave juice and bagasse) is collected and put into the distillation equipment. Distillation separates ethanol and volatile compounds. The distillation is done in a pot still and rectifying column consisting of a kettle to hold the fermented wort and a condenser or a plate heat exchanger. Some factories use a steam coil to heat the wort, but most heat the kettle in a stove. Mezcal is distilled twice. In the first distillation, the alcohol concentration is between 20 to 40% by volume, after removing the first (heads) and last extraction (tails). The second distillation brings the concentration to 45 to 60 % by volume. 

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