Distillation condensers

An enrichment is defined as a separation process that results in the increase in concentration of one or mote species in one product stream and the depletion of the same species in the other product stream. Neither high purity not high recovery of any components is achieved. Gas enrichment can be accompHshed with a wide variety of separation methods including, for example, physical absorption, molecular sieve adsorption, equiHbrium adsorption, cryogenic distillation, condensation, and membrane permeation. 

There are many chemicals, by lowering suitable as carriers. Their bp is one of the principal criteria in selection. If bp is too low, the compound will evaporate from the dyebath at dyeing temperatures, and will be lost before it is effective in its role as a carrier. It may also steam distill (condense on the cooler parts of the equipment) and cause drips that will spot the fabric. On the other hand, if the bp is too high, the compound cannot be removed from the fabric under normal plant drying conditions and will affect lightfastness of finished goods, leave residual odor, and possibly cause skin irritation to the wearer. 

Chou, Yung-ho, Understand the Potential of Sub-Cooled Distillate Condensate, Chem. Eng. Prog. V. 88, No. 6 (1992), p. 5. 

Fractional distillation condenser, 131 Fractional distillation receiver, 132 Fractionating column, 132 Frozen surfaces, 82... 

A condenser of the type shown in Figure 59 is often called a fractional distillation condenser and was advocated by H. Jackson, Professor of Chemistry at King s College, London—hence the condenser is sometimes called a King s College condenser. It can be used as an ordinary condenser and as a reflux condenser. To make it, a... 

Diazomethane Follow essentially Aldrich Chemical Company s procedure for the Preparation of ethereal-alcoholic solution of diazomethane A 25-mL volume of ethanol is added to a solution of 5 g of potassium hydroxide in 8 mL of water in a 100-mL distillation flask fitted with a dropping funnel and a distillation condenser. The lower end of the condenser extends through and just below the neck of a 250-mL Erlenmeyer receiving flask, the latter being cooled in an ice-bath. The distillation flask containing the alkaline solution is heated in a water-bath to 65 °C and the contents of the flask are agitated with a magnetic stirrer. A solution of... 

Under what circumstances might a distillation condenser be orientated vertically or horizontally. 

C. p-Bromodiphenylmethane. A 2-1. three-necked flask fitted with a distillation condenser, a thermometer, and an efficient mechanical stirrer is charged with 1.1 1. of diethylene glycol (Note 7) and a solution of 190 g. of potassium hydroxide in 100 ml. of water. The mixture is stirred, and water is distilled until the internal temperature reaches 180°. The resulting solution is allowed to cool to 100° or below, and 146 g. (0.40 mole) of l-/>-bromophenyl-l-phenyl-2,2,2-trichloroethane (Note 8) is added. The condenser is set for reflux, and the mixture is stirred and heated to boiling for 5 hours (Note 9). The hot solution is then poured onto 3 kg. of cracked ice, and the mixture is allowed to stand overnight. The oily layer is separated and dissolved in ether (any insoluble material is discarded), and the aqueous layer is extracted with 250 ml. of ether. The combined ethereal solution and extracts are dried over calcium chloride and filtered. The ether is removed under reduced pressure on a hot water bath. The product is distilled under reduced pressure b.p. 120-130° (3 mm.), 155-163° (13 mm.) (Note 10), n2id 1.6028, dH 1.342. The yield is 74-79 g. (75-80%) (Note 11). 

The finished product is centrifuged and purified via a number of processes, including filtration, fractional distillation, condensation, crystallization, and chromatographic separation techniques. The purified API is tested and then it is ready to be formulated into the finished dosage form, as discussed in Section 10.6. Exhibit 10.5 illustrates some of the typical reagents for API manufacture and Exhibit 10.6 presents selected chemical reactions as examples of the... 

Filtration/Fractional Distillation/Condensation Filters are used to remove solid particles from a solvent. The use of 0.2 jum filters can remove microbial contamination. Filtered solutions can be fractionally distilled and condensed to obtain the API. 

Methylphenobarbitone. 1 mole of phenobarbitone (232.23 g) is dissolved in 2.5 liters of 95% (not dry) ethanol. To this is added a solution of 45 g NaOH (sodium hydroxide) in 500 ml of 95% ethanol. This mixture is heated, with stirring, until reflux is achieved. 70 g of dimethyl sulphate is added dropwise and refluxing is continued for 3 hours after this addition. Change the reflux condenser into a distillation condenser and distill the ethanol from the mixture. Add water and pour into an ice-hydrochloric acid mixture at 0°. Recrystallize the resulting precipitation, after collection by filtration, from boiling water using decolorizing charcoal. Yield 70% of theoretical, mp 178-181°. 

Sulfur trioxide is prepared in the laboratory by heating fuming sulfuric acid, condensing its vapors, and collecting in a cool receiver. When vapors are condensed below 27°C in the presence of trace moisture, aU three polymorphic phases of SO3 are produced. They can be separated by fractional distillation. Condensation of the vapors above 27°C forms the hquid variety of gamma-sulfur trioxide. 

Production of Citrus Essence Oils. Distillative concentration of citrus juices yields essence oils, which separate from the aqueous phase in the receiver when the distillate condenses. The composition of essence oils is similar to that of peel oils, but the essence oils usually contain larger quantities of aliphatic ethyl esters (e.g., ethyl butyrate in orange essence oil). Thus, their aroma resembles that of a particular juice more than that of peel oils. 

For the manufacture of blackpowder the sulphur used should be of highest purity, refined by distillation. Crude sulphur (which usually contains 2-5% of impurities) is distilled from retorts heated to a temperature of400°C. The receiver should be maintained at a temperature above 115°C (120-130°C), i.e. above the melting point of sulphur (114-115°C). Under these conditions the distillate condenses to a liquid which is then cast into sticks or blocks. This is the only form of sulphur suitable for the manufacture of blackpowder. If the receiver temperature is lower, the sulphur distilled from the retort condenses as flowers of sulphur which always contain a little S02) and even traces of H2S04 (the substance is easily oxidized due to its large surface area). Sulphur in this form is therefore slightly hygroscopic and acidic, and is unsuitable for the manufacture of blackpowder. 

The reaction mixture is then cooled to room temperature, the reflux condenser is replaced with a distillation condenser equipped with a vacuum take-off, and most of the solvent is removed under reduced pressure (ca. 100 mm.) until a thick paste is obtained. The mixture is then cooled in an ice water bath, and 150 ml. of ether is added. Cold water (200 ml.) is placed in the addition funnel, and initially the water is added dropwise (Caution Vigorous evolution of hydrogen) until the excess sodium hydride is destroyed then the remainder of the water is added more rapidly (Note 5). 

Fig. 69. Production diagram of the semicontinuous production of polyphenyl-silsesquioxane obtained by the hydrolytic condensation of phenyltrichlorosilane 1,7- batch boxes 2 - hydrolyser 3 - separator 4 - flusher 5 - separator settling box 6 - distillation condenser tank 8 - cooler 9, 11, 12 - collectors 10 - settling box...

The most advanced two-stage process involves close coupled operation with a disposable slurry catalyst (typically iron and/or molybdenum) added with the feed coal and an integrated hydrotreater to treat the distillate condensed from the gaseous phase from the... 

The submitters reported that successive 2.5-1. portions of distillate were filtered, and the following weights of product were obtained 14.5, 10.7, 9.0, and 2 g., or 36.2 g. in 10 1. From one run the checkers obtained 19, 12, 6, and 2 g., or 39 g. In some runs it was necessary to collect 15-30 1. of distillate in order to obtain a 30-g. yield. The submitters report that unchanged amine, if present during the steam distillation, condenses with the nitroso compound, giving tarry products, and the yield of nitroso compound is reduced. 

When the addition of dimethyl sulfate Is complete, stirring was continued for 1 hour at 20-25 C. Then the temperature was raised to 60-65 during 10 minutes and was kept at this value until the evolution of carbon dioxide ceased. After the addition of 25 ml of cold water, the reaction flask was cooled rapidly In an Ice bath and 10 ml of ethanolamlne was added. The resultant crystalline slurry was removed from the flask and the apparatus was rearranged using a distilling condenser, receiving flask, and a heating bath. 

Kanani DM, Nikhade BP, Balakrishnan P, Singh G, and Pangarkar VG. Recovery of valuable tea aroma components from steam distillation condensate by pervaporation. Ind. Eng. Chem. Res. 2003 42(26) 6924-6932. 

The apparatus used for steam distillation usually consists of a three-necked flask with a steam inlet and a distillation condenser. The steam... 

Simple extraction is often a rather inefficient process and may be modified to magnify the effect of one extraction. This may be done in either of two ways by using continuous extraction, in which the solvent is recycled through the solution by the use of a distillation-condensation cycle or by countercurrent extraction, in which the original solution and the extracting solvent are permitted to flow in opposite directions through a tube designed to promote contact between the phases. These methods will be described in turn. 

Excitation spectrum In fluorescence spectroscopy, a plot of fluorescence intensity as a function of excitation wavelength. Exhaustive extraction A cycle in which an organic solvent, after percolation through an aqueous phase containing the solute of interest, is distilled, condensed, and again passed through the aqueous phase. 

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