Silver nitrate impregnation

The dipping unit can also be employed to impregnate adsorbent layers. It is easy in this way to produce tungstate- [127] or silver nitrate-impregnated layers for separating oligosaccharides or unsaturated compounds. 

Phosphomolybdic acid essential oil components stabilization of the silver nitrate-impregnated adsorbent layer [207]... 

The reagent can be employed on silica gel, silver nitrate-impregnated silica gel, carboxymethylcellulose-containing silica gel, kieselguhr and Si 50000 layers RP phases are not suitable. 

Note Rhodamine B is a universal reagent that can be used on silica gel, talc, starch [5] and cellulose layers, just as on urea [1] or silver nitrate-impregnated [7] phases. Liquid paraffin-impregnated silica gel and RP layers are less suitable, since the background to the chromatographic zones is also intensely colored. It is often possible to increase the detection sensitivity by placing the plate in an atmosphere of ammonia after it has been sprayed or dipped, alternatively it can be oversprayed with sodium or potassium hydroxide solution. 

One of the inconveniences of this method is the formation of olefinic side products, (see below) but the desired saturated compounds can be readily isolated by chromatography on silver nitrate impregnated silica gel... 

Mixtures of phosphoglycerides can be separated using a chloroform-methanol-water mixture, the proportions of which may be varied to suit the sample constituents (e.g. 65 25 4). Acetone is sometimes included in the solvent and silver nitrate-impregnated plates can be used. Acetic acid (1-4%) is also a useful additive to effect the separation of neutral phosphoglycerides... 

For the recifeiolide synthesis, the oxazole carbanion was alkylated with iodo THP ether (340) (an 85 15 mixture of (E)- and (Z)-isomers). Acid hydrolysis of the THP group, photooxygenation and cyclization gave a mixture of (E)- and (Z)- ( )-recifeiolide (341) from which the pure (E)-form could be isolated by chromatography on silver nitrate-impregnated silica gel (Scheme 74). 

Figure 11.26 Performance of a 37 m2 hollow fiber silver-nitrate-impregnated facilitated transport membrane for the separation of propylene/propane mixtures. The feed pressure was 5-13 atm the permeate was a hexane liquid sweep stream. The vertical dotted lines show when the membrane was regenerated with fresh silver nitrate solution [27]. Reprinted with permission from R.D. Hughes, J.A. Mahoney and E.F. Steigelmann, Olefin Separation by Facilitated Transport Membranes, in Recent Developments in Separation Science, N.N. Li and J.M. Calo (eds) (1986). Copyright CRC Press, Boca Raton, FL...

AgX) Silver nitrate impregnated silica Purex Silver reactors Charcoal Organic sorbers AgXI Agl Agl, AgI03 Iodine loaded charcoal, I2 Iodine loaded material, I2 zeolite ... 

Thin Layer Chromatography is used by major manufacturers of radiolabeled vitamin D3 (48) for monitoring purity. The systems described are 1) silica gel G with 10% acetone in hexane 2) silica gel G with acetone-hexane 1 1 and acetone-chloroform 1 1 3) silver nitrate-impregnated silica gel G with chloroform or chloroform-acetone 9 1 and 4) silica gel saturated with silicone oil using 4 1 acetone-water. It may be mentioned that these operations are carried out under very carefully controlled conditions to prevent or minimize decomposition. TLC is an excellent technique for separating vitamin Do from interfering materials, but it has to be used with due care in the quantita-... 

Figure 2. Sulfide concentrations measured on silver nitrate impregnated filters in series. Data shown from sample collected in Miami on 10/8/86 for 170 min at 7.81/min. The front filter extract was diluted by a factor of four.

Henon, G., Recseg, K. and Kovari, K. (2001) Wax analysis of vegetable oils using liquid chromatography on a double absorbent layer of silica gel and silver nitrate-impregnated silica gel. J. Amer. Oil Chem. Soc., 78(4), 401 110. 

Among the various laboratory procedures used for studying fatty acids, concentrations by chromatography on silver nitrate impregnated silica gel, or equivalent (87), are too expensive to scale up although effective for fish oils (88), they and mercuric adducts (89) would not be acceptable for health and safety reasons. 

The silver nitrate-impregnated silica gel (25%) was applied to the separation of some sesquiterpenes. It was found that a mixture of p-selinene and caryophyllene could be separated satisfactorily by development with n-hexane and benzene-acetone (95 5, v/v) as mobile phases. After the development, the plates are dried in air and then sprayed with a solution of chlorosulfonic acid in acetic acid (1 2) and heated at 130°C. Usually, different... 

The silver nitrate-impregnated silica gel G was used to obtain a separation with a group of tetracyclic triterpene alcohols, which could not be separated on untreated silica gel. However, on silica gel G (Ag impregnated), the Rf values were sufficiently different so as to enable the substances to be identified separately. Chloroform was used as the mobile phase. The tetracychc triterpenes were detected by spraying with one of the three reagents 50% sulfuric acid in water or 10% phosphomohbdic acid in ethanol or chlorosulfonic and acetic acids (1 2) followed by heating in an oven at 150°C. ... 

Silver nitrate-impregnated silica gel has also been used successfully in the separation of some classes of compounds that contain double bonds in their structures. Thus it was used in the separation of glycerides and isomers of unsaturated fatty acid esters. The 2-D TLC on adjacent layers of silica gel G and sihca G impregnated with 5% of silver nitrate was used for development. The silica gel G layer covered a surface of 3 x 20 cm and the difference of the surface of 17 x 20 cm was covered with silica gel G impregnated with 5% AgNOs. The first direction was performed on silica gel G with petroleum ether-diethyl ether (9 1, v/v) as eluent. The second direction was carried out on the impregnated silica gel G and developed twice with the same eluent as in the first direction. After the first direction, the mixture was... 

Samples A and C have been characterized by XRD after the wash-coating procedure and before silver nitrate impregnation. Mullite (major phase) and... 

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