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Partition column chromatography

In a particular partition chromatography column, the volumes of mobile phase, stationary phase, and inert phase are in the ratio A, A/ of 0.20 0.05 0.75 and the HETP is 0.0050 cm. Two substances having partition coefficients of 1.50 and 1.55 are to be separated. Calculate (a) the values for the two substances, (b) the volume of eluent required to bring each of the bands in turn to a point 10.0 cm down a column of total area 1.0 cm, (c) the volume of eluent required to wash all but 0.13% of the leading component from a 30 cm column, and (d) the % of the lagging component that has been removed under the conditions of part c. [Pg.164]

This served to further fractionate the azo pigments of the B type as obtained from step II. Reverse-phase partition chromatography columns were prepared from silicone-treated celite and from a multicomponent solvent system, pH 3.4. The latter contained n-octanol, diisopropyl ether, ethyl acetate, methanol, and aqueous 0.2 M acetic acid in proportions of 1 2 2 3 4 by volume. [Pg.362]

Paper strip chromatography showed approximately equal amounts of substrate and a more polar product (A -pregnadiene-9a-fluoro-11/3,l6a,17a,21-tetrol-3,20-dione 16,21-diacetate) together with very small amounts of two less polar products. Partition chromatography of 0.25 gram of the residue (diatomaceous earth column system 2 parts ethyl acetate,... [Pg.1525]

PCS. Partition chromatography on starch column 196, 261). MBA. Microbiological assay. [Pg.18]

The extracted crude luciferin was purified by Anderson s benzoy-lation method mentioned above (Anderson, 1935), followed by partition chromatography on a cellulose powder column using a mixture of ethyl acetate-ethanol-water (5 2 3 Tsuji, 1955) as the solvent, again in a hydrogen atmosphere. The luciferin obtained (3 mg) was highly pure by paper chromatography, and appeared suitable for crystallization. I... [Pg.55]

Figure 7. Infrared spectrum of pyrethrin I Isolated after dual partition chromatography First partition column. Celite-acetonitrile-hexane Second partition column. Silicic acid-nitromethane-hexane (with 5% acetone). Corresponds to peak 3 of gas chromatographic separation of pyrethrum mixture... Figure 7. Infrared spectrum of pyrethrin I Isolated after dual partition chromatography First partition column. Celite-acetonitrile-hexane Second partition column. Silicic acid-nitromethane-hexane (with 5% acetone). Corresponds to peak 3 of gas chromatographic separation of pyrethrum mixture...
Other modes of LC operation include liquid-liquid partition chromatography (LLC) and bonded phase chromatography. In the former, a stationary liquid phase which is immiscible with the mobile phase is coated on a porous support, with separation based on partition equilibrium differences of components between the two liquid phases. This mode offers an alternative to ion exchange in the fractionation of polar, water soluble substances. While quite useful, the danger exists in LLC that the stationary phase can be stripped from the column, if proper precautions are not taken. Hence, it is typical to pre-equil-ibrate carefully the mobile and stationary phases and to use a forecolimn, heavily loaded with stationary phase 9). [Pg.227]

Residue analytical methods for neonicotinoids in crops, soil and water samples have been developed. The basic principle of these methods consists of the following steps extraction of the crop and/or soil samples with acetone or the other organic solvent, cleanup by liquid-liquid partition or column chromatography, and quantitative analysis by high-performance liquid chromatography with ultraviolet detection (HPLC/UV). Simple column cleanup procedures are used to improve the accuracy and sensitivity of these methods. [Pg.1128]

Sediment Soxhlet extraction clean-up by liquid-liquid partition, alumina column chromatography GC/NPD 81-97 Muiretal. 1981... [Pg.327]

At Sirius, a dedicated instmment (Profiler LDA) has been developed for the rapid measurement of log D by liquid-liquid partition chromatography. In this instrument the column is coated with a layer of octanol, and the retention times are therefore tmly related to octanol/water partitioning. Although the method used was first described 25 years ago [29], it has been difficult to apply in an automated system because of the tendency of octanol to be flushed from the column by the eluent, thus requiring frequent renewals of the octanol coating. In our method, the octanol coating is kept in place by reversing the direction of the eluent after each... [Pg.30]

A sensitive method was described for the detection and estimation of residues of niclosamide in bananas involving extraction of niclosamide, purification of the extract by solvent partition and column chromatography, formation of the hepta-fluorobutyryl derivative of 2-chloro-4-nitroaniline in 99% yield, and determination of the derivative by gas liquid chromatography with electron capture detection. [Pg.90]

Donovan, S.F., Pescatore, M.C. (2002) Method for measuring the logarithm of the octanol-water partition coefficient by using short octadecyl-poly(vinyl alcohol) high-performance liquid chromatography columns. J. Chromatogr. A, 952, 47-61. [Pg.608]

The ether solution and fractions taken during the subsequent distillation may be assayed by gas-liquid partition chromatography on a 0.8-cm. x 200-cm. column heated at 120° and packed with nonyl phthalate supported on ground firebrick. [Pg.28]

A bottle of fizzy drink going flat is a fairly trivial example of partition, but the principle is vital to processes such as reactions in two-phase media or the operation of a high-performance liquid chromatography column. [Pg.206]

Partition chromatography Ion exchange chromatography Paper chromatography Open-column chromatography High-performance liquid chromatography... [Pg.334]

See other pages where Partition column chromatography is mentioned: [Pg.2193]    [Pg.2036]    [Pg.2193]    [Pg.2036]    [Pg.546]    [Pg.547]    [Pg.51]    [Pg.820]    [Pg.3]    [Pg.13]    [Pg.16]    [Pg.13]    [Pg.217]    [Pg.17]    [Pg.6]    [Pg.294]    [Pg.188]    [Pg.195]    [Pg.60]    [Pg.687]    [Pg.218]    [Pg.352]    [Pg.327]    [Pg.390]    [Pg.452]    [Pg.328]    [Pg.236]    [Pg.554]    [Pg.266]    [Pg.287]    [Pg.234]    [Pg.219]    [Pg.449]    [Pg.201]    [Pg.315]   


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