Gauze pack

T] Check of 132 data points showed average deviation 14.6% from theory. Johnstone and Pig-ford [Ref. 105] correlation (5-22-D) has exponent on Nue rounded to 0.8. Assume gauze packing is completely wet. Thus, = a, to calculate Hq and Same approach may be used generally applicable to sheet-metal packings, but they will not be completely wet and need to estimate transfer area. 

Hept-l-ene [592-76-7] M 98.2, b 93 /771mm, d 0.698, n 1.400. Distd from sodium, then carefully fractionally distd using an 18-in gauze-packed column. Can be purified by azeotropic distn with EtOH. Contained the 2- and 3-isomers as impurities. These can be removed by gas chromatography using a Carbowax column at 70°. 

Carefully fractionated through a gauze-packed column. Redistil and collect in weighed glass vials and seal. Keep away from moisture. It undergoes alkyl exchange with alcohols and forms azeotropes, e.g. with MeOH the azeotrope consists of 70% (MeO)3B and 30% MeOH with b 52-54"/atm, d 0.87. [J Chem Soc 2288 7952 Chem Ind (London) 53 7952 J Am Chem Soc 75 213 7955.] Also dried with Na, then distilled. 

Figure 5-4b shows details of arresting elements of wire gauze and wire gauze packs. 

Figure 9-65. Performance of structured gauze packing vs. Pall rings. Used by permission of Biiiet, R., Chemical Engineering, V. 79, No. 4 (1972) p. 68 ali rights reserved.

For vacuum distillations the maximum allowable pressure drop will be determined by the process requirements, but for satisfactory liquid distribution the pressure drop should not be less than 8 mm water per m. If very low bottom pressures are required special low pressure-drop gauze packings should be considered such as Hyperfil, Multifil or Dixon rings see Volume 2, Chapter 4. 

The details of the experimental apparatus and procedures are outlined in another paper (76). The reactor consisted of a quartz tube with an inside diameter of 18 mm which held the monolith or gauze pack. The reactor was operated at a steady state temperature which is a function of the heat generated by the exothermic reactions and... 

Three basic types of catalysts were studied in these experiments Pt-10% Rh gauzes, foam monoliths, and extruded monoliths. The gauze catalysts were 40 mesh (40 wires per inch) or 80 mesh R-10% Rh woven wire samples which were cut into 18 mm diameter circles and stacked together to form a single gauze pack 1 to 10 layers thick. Gauze catalysts are used industrially in the oxidation of hftls to NO for HNO3 production and in the synthesis of HCN from NH3, CH4, and air. 

J.L. Bravo, J.A. Rocha and J.R. Fair, Mass transfer in gauze packings, Hydroc. Proc., Janvier, (1985) 91. 

The thickness of the liquid film on the rotor packing helps determine mass transfer rates. Film thickness can be shown to be inversely proportional to rotor speed to the 0.8 power (17). Visual measurements using a video camera attached to the rotor show a water film thickness of 20-80 microns on foam metal packing and 10 microns on wire gauze packing (15). Theoretical models estimate similar film thickness values (13,18,19). Film flow is expected to be laminar. In addition to rotor speed, liquid flow rate and fluid properties affect the film thickness (14). 

Hgim ftuS Wire-mesh structured packing . <0) Saber wire gauze packing BX (6) Sulzer wire gauze packing CY. IParta a and o, courtesy of Sober Chemteeh.)... 

The extraction column to be used in the process will have an internal gauze packing - Sulzer BX, that was chosen due to its large interfacial area, high porosity and low pressure drops. 

The diameter of the column may be accurately calculated with the knowledge of the maximum capacities attained by the used gauze packing under the current extraction conditions. Although there is no experimental data available for our system, measured flooding data have been lately published in the literature for the system com seed oil/C02 at high... 

Pressure drop through wire-gauze packing (95)(0.4 mmHg/stage) = 38... 

Heights of transfer units for the individual phases were obtained from Eq. 13.164 and 13.165, and Eq. 13.167 provides the height of an overall transfer unit. For the gauze packings, with spreading aided by capillary action, interfacial area a = Up (specific surface area from Table 13.15). For sheet metal packings, which do not promote as much liquid spreading, empirical correction factors were proposed by Fair and Bravo (1990) ... 

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