Packed Distillation Columns

Cost of solvent extraction auxiliaries Cost of absorbtion and distillation column packing, supports and distributors Cost of tanks (surge, etc.)... 

Raschig ring -as distillation column packings [DISTILLATION] (Vol 8)... 

Ceramic materials also are being used in a limited fashion by the chemical process industries for such applications as high-tcmpcrature (I.KXTC) heal exchangers, as absorption and distillation column packing, catalyst supports, and high-temperature refractory linings. 

Fuchigami Y. Hydrolysis of methyl acetate in distillation column packed with reactive packing of ion exchange resin. J Chem Eng Japan 1990 23 354-358. 

When compared to conventional systems (such as strippers, scrubbers, distillation columns, packed towers, bubble columns, evaporators, etc.), membrane contactors present several advantages, as reported in Figure 20.3. However, some drawbacks have also to be taken into account, as shown in Figure 20.4. 

Eckert, J.S. Selecting the proper distillation column packing. Chem. Eng. Prog. 1970, 66 (3), 39 4. 

Isolation of Volatiles. An aliquot of blended pulp (1.2 kg) was diluted with distilled water (700 mL) in a 3-L three-neck flask and vacuum distilled (25-30°C/l mm Hg). Distillation continued for 2.5 to 3 h yielding approximately 500 mL of distillate which was collected in two liquid nitrogen cooled traps. A total of 3.6 kg of fruit pulp was distilled in three batches. The distillates were combined and immediately frozen until use. The combined distillate was extracted in 250 mL batches for 20 h with 60 mL trichloro-fluoromethane (Freon 11, b p 23.8°C) using a continuous liquid-liquid extractor. The trichlorofluoromethane was distilled through a 120 x 1.3 cm glass distillation column, packed with Fenske helices, prior to use. Each extract was carefully concentrated to approximately 100 pL by distillation of solvent using a Vigreux column (16 cm), and a maximum pot temperature of 30°C. 

The adapter bearing the dry ice condenser and dropping funnel is removed and replaced by a 16 cm. x 2 cm. distillation column packed with glass helices (Note 7) and connected to an efiicient air-cooled condenser. The condenser has a 100-ml. receiver and is connected to a trap cooled in dry ice and protected by a drying tube to condense unreacted cyanogen chloride. The reaction flask is heated for about 1 hour while the temperature is gradually increased to 110-115°. At this point, cyanogen chloride is bubbled into the reaction mixture at the rate of about 0.010 mole/min. (Note 8). The temperature of the flask is raised to... 

Fig. 75. Distillation column packed with Raschig rings.

FKiURK 2.11 Total reflux distillation column. Packing segment of height Az shown, with associated flows and compositions as indicated. 

Y. Fuchigami, Hydrolysis of Methyl Acetate in Distillation Column Packed with Reactive Packing of Ion Exchange Resin, J. Chem. Eng. Jpn., 1990, 23, 354-358. 

In yet another case, the vapor traffic going up the column is creating the maximum pressure drop that can be operated successfully through a distillation tray or through a distillation column packing. A higher flow rate of vapor would hold liquid up in the column, and it would be flooded. The column must be kept below flooding. This is another constraint. 

TaUel Requirements for a catalytic reactive distillation column packing ... 

Figure 6-21 Distillation column—Packed random saddle design...

In a hood, behind a safety shield, in a 250-ml flask fitted with a thermometer, a fine capillary tube connected to a drying tube for an air bleed, and a distillation column packed partially with copper cloth (see above) topped with a spray trap and a total reflux, partial take-off distillation head are placed 100 ml of glacial acrylic or methacrylic acid and 1 gm of A,N -diphenyl-/ -phenylenediamine or phenothiazine. 

Bolles WL, Fair JR. Performance and design of packed distillation columns. 3rd Int. Symp. on Destination, London, April (1979). EFCE Publications Series No. 3, vol. 2, p. 3.3./35-89 Eckert JS. Selecting the proper distillation column packing. Chem. Eng. Progr., vol. 66 (1970) no. 3,... 

The recovery of acetic acid from its dilute aqueous solutions is a major problem in both petrochemical and fine chemical industries. Saha, et al. (2000) developed conventional methods of recovery of 30% acetic acid by reaction with n-butanol and isoamyl alcohol in a reactive distillation column using macroporous ion-exchange resin, Indion 30, as a catalyst bed, confined in stainless steel wire cages. They found that recovery of acetic acid was enhanced by reactive distillation compared to the batch operation. Hanika et al. (1999) studied the esterification butyl alcohol with acetic acid in a pilot plant using a reactive distillation column packed with commercial catalysts (KATPAK and CY). It was found that butyl acetate could be recovered in very high purity. This study had resulted in the development of a new technology for the manufacture of butylacetate. 

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