Absorption column assembly

Industrial analysis of hydrocarbon gases 25 years ago was limited almost to Orsat-type absorptions and combustion, resulting in crude approximations and inadequate qualitative information. The more precise method of Shepherd (56) was available but too tedious for frequent use. A great aid to the commercial development of hydrocarbon gas processes of separation and synthesis was the development and commercialization of high efficiency analytical gas distillation units by Podbielniak (50). In these the gaseous sample is liquefied by refrigeration, distilled through an efficient vertical packed column, the distillation fractions collected as gas and determined manometrically at constant volume. The operation was performed initially in manually operated units, more recently in substantially automatic assemblies. 

Ruzicka, the head of one of the pioneering teams In FIA, designed various assemblies for the preconcentration of traces of metal Ions prior to their determination by atomic absorption or ICP spectroscopy in a variety of liquid matrices by use of small columns (5 mm x 2 mm I.D.) packed with the chelating resin Chelex-100 (50-100 mesh). The most Interesting of such assemblies [22] are shown in Fig. 4.14. The first assembly (Fig. 4.14a), the simplest of all, features a single line with two serial Injection valves (Ii for insertion of sample and Ij for Introduction of the eluent) prior to the column on which the analytes are retained. First the sea water sample is Injected and driven to... 

As an example a density difference A/9 < 0.1 kg/L is considered to be too small for phase separation in a countercurrent column. For Ap < 0.1 kg/L, the value m(x) = 0. Therefore the result for the whole method is zero. This means that absorption can not be used at such a small density difference for regeneration. The assembled methods for regeneration of the supercritical solvent are not comprehensive. They can be extended to other methods for regeneration. The proposed scheme provides a general methods of selecting and evaluating regeneration methods. 

The FID collector assembly was modified to connect, via Swage-lok fittings, to a small bore (0.027-inch i.d.), heated, programmable, stainless steel transfer tube, manufacured by Chemical Data Systems, Inc., Oxford, Pa. 19363. The GC injection ports, FID detector, and transfer tube were maintained at lOO C for all experiments conducted. The total column effluent from the GC was conducted through the transfer tube to the detector, a Perkin-Elmer model 360 atomic absorption spectrophotometer fitted with a deuterium background corrector and a HGA-2100 graphite furnace atomizer employing a temperature dial control power supply. 

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