Simple distillation condenser

Experimental Determination of Boiling-point. Unless only minute quantities of the liquid are available cj. p. 60), the boiling-point is usually determined by simple distillation. For this purpose, the apparatus shown in Fig. 2 is assembled. A distillation flask A of suitable size is fitted to a water-condenser B, the water supply of which is arranged as show-n. An adaptor C is sometimes fitted in turn to the condenser, so that the distillate... 

Most students will be familiar with simple distillation from their practical inorganic chemistry. Other students should determine the boiling-point of acetone (56°), using a water-bath and water-condenser, or of benzene (81 ), using a sand-bath and water-condenser, and finally of either aniline (184 ) or nitrobenzene (210 ), using for both these liquids a sand-bath and air-condenser. 

Fig. 23(D) shows a simple distillation apparatus with an adaptor fitted to the lower end of the condenser. This apparatus can also be used for the recovery of solvents, or for the concentration of a solution with collection of the distilled solvent.

Simple distillation. The assembly shown in Fig. II, 60, 1 is of general utihty for very volatile liquids the Liebig s condenser may be replaced by a double surface condenser. 

Setup your glassware for simple distillation with a claisen adapter, three way adapter, pressure-equalized addition funnel, water cooled condenser, vacuum adapter and receiver flask to catch any condensed solvent vapors. 

The pressure used in producing gas wells often ranges from 690— 10,300 kPa (100—1500 psi). The temperature of the inlet gas is reduced by heat-exchange cooling with the gas after the expansion. As a result of the cooling, a liquid phase of natural gas liquids that contains some of the LPG components is formed. The liquid is passed to a set of simple distillation columns in which the most volatile components are removed overhead and the residue is natural gasoline. The gas phase from the condensate flash tank is compressed and recycled to the gas producing formation. 

Distillation is a method of separation that is based on the difference in composition between a Hquid mixture and the vapor formed from it. This composition difference arises from the dissimilar effective vapor pressures, or volatihties, of the components of the Hquid mixture. When such dissimilarity does not exist, as at an a2eotropic point, separation by simple distillation is not possible. Distillation as normally practiced involves condensation of the vaporized material, usually in multiple vaporization/condensation operations, and thus differs from evaporation (qv), which is usually appHed to separation of a Hquid from a soHd but which can be appHed to simple Hquid concentration operations. 

FIG. 13-1 Schematic diagram and nomenclature for a simple distillation column with one feed, a total overhead condenser, and a partial rehoiler. 

In distillation operations, separation results from differences in vapor-and liquid-phase compositions arising from the partial vaporization of a hquid mixture or the partial condensation of a vapor mixture. The vapor phase becomes enriched in the more volatile components while the hquid phase is depleted of those same components. In many situations, however, the change in composition between the vapor and liquid phases in equihbrium becomes small (so-called pinched condition ), and a large number of successive partial vaporizations and partial condensations is required to achieve the desired separation. Alternatively, the vapor and liquid phases may have identical compositions, because of the formation of an azeotrope, and no separation by simple distillation is possible. 

Consider now the consequences of placing simple distillation columns (i.e. one feed, two products, one reboiler and one condenser) in different locations relative to the heat recovery pinch. The separator takes heat Qreb into the reboiler at temperature Treb and rejects heat Qcond at a lower temperature Tcond There are two possible ways in which the column can be heat integrated with the rest of the process. The reboiler and condenser can be integrated either across, or not across, the heat recovery pinch. 

Performing a simple distillation experiment is every chemist s delight. We gently warm a mixture of liquids, allowing each component to boil off at its own characteristic temperature (the boiling temperature r(boii)). Each gaseous component cools and condenses to allow collection. Purification and separation are thereby effected. 

A. AcetamidoaceUme. A mixture of 75.0 g. (l.O mole) of glycine (Note 1), 475 g. (485 ml., 6 moles) of pyridine (Note 1), and 1190 g. (1.1 1., 11.67 moles) of acetic anhydride (Notes 1 and 2) is heated under reflux with stirring for 6 hours (Note 3) in a 3-1., three-necked, round-bottomed flask. The reflux condenser is replaced by one set for downward distillation, and the excess pjnidine, acetic anhydride, and acetic acid are removed by distillation under reduced pressure. The residue is transferred to a simple distillation apparatus such as a Claisen flask and is distilled to give 80-90 g. (70-78%) of a pale yellow oil, b.p. 120-125° (1 mm.). This product is of satisfactory purity for use in step B. 

Figure 2(b) shows a simple distillation column with two degrees of freedom provided by the reboiler and condenser. For example, for liquid feed, the top product might be set at an intermediate value between zero and the amount of feed although no upper limit would exist on reboiler vapor, a lower limit would exist corresponding to zero reflux. It would be quite easy to set the reboiler vapor below this limit, unless a calculation had been made to determine what the limit was. Such a calculation would not be too difiicult in this case. 

The condenser and the addition funnel are removed and replaced by a simple distillation head and a condenser. 

A. Cyclopentadiene. Two hundred milliliters (195 g.) of technical dicyclopentadiene (Note 1) is placed in a 500-ml. twonecked round-bottomed flask equipped with thermometer and an upright Friedrichs-type condenser (through which water at 50° (Note 2) is circulated). The ground-glass (Note 3) outlet of the Friedrichs condenser is connected to the side arm of a simple distilling head fitted with a thermometer and attached to an efficient water-cooled condenser held in a vertical position. At the lower end of this condenser is a receiver which consists of a carefully weighed 500-ml. two-necked round-bottomed flask immersed in a Dry Ice bath (Note 4) and protected from the air by a calcium chloride drying tube. 

SIMPLE DISTILLATION. Distillation in which no appreciable rectification of tile vapor occurs, i.e., the vapor formed from the liquid in the still is completely condensed in the distillate receiver and does not undergo change in composition due to partial condensation or contact with previously condensed vapor. 

Each column performs a simple split (i.e., we have simple distillation columns). The thermodynamic state of the feed streams, distillates and bottoms streams, and the type of condenser used in each column are assumed to be known. 

Notes. (1) Isoprene is purchased in sealed capsules. These are usually stored in a refrigerator and only removed just prior to opening and redistillation of the isoprene. A simple distillation unit may be employed using a double surface condenser, the... 

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