Gels Impregnated with Metal Salt Solutions

Gels Impregnated with Metal Salt Solutions... 

To obtain composites of carbon with metal nanoparticles, organic gels can be impregnated with metal salt solutions before drying and pyrolysis processes... 

Sulfonamides can be analyzed both by NP TLC (on silica gel, alumina, polyamide, and Florisil layers) and by RP TLC (on silanized sihca, RP-2, RP-8, and RP-18 layers). Some sulfonamides have been separated by TLC on silica or polyamide impregnated with metal salts. Both aqueous and non-aqueous eluents are applied. Detection of sulfonamides can be performed on fluorescence layers at 254 nm and after derivatization with, for instance, fluorescamine solution at 366 nm. 

A number of methods have been reported in the literature for improving the thermal stability of acrylic fibers. For example, impregnating wet-spun fibers in the gel state with salts of metals from group II in the periodic table of the elements [496] or sodium sulfide solution [487] have been reported. Also, dried fiber can be impregnated with sulfuric acid solutions of formamide [488], phosphates or borax [489], or organotin salts [490]. 

For practical (real) catalyst systems, precipitation, ion exchange, impregnation and sol-gel processing procedures are used. In precipitation methods, a hydroxide or a carbonate of a metal may be precipitated from a solution of a metal salt onto the support material held in the solution. Thus, a copper-silica catalyst may be prepared using a Cu-nitrate solution in which silica is suspended. Additives of any alkali cause the precipitation of copper hydroxide onto the silica support. This is then dried and normally reduced in hydrogen at moderate temperatures ( 400-500 °C) to form the catalyst. In co-precipitation techniques , the support is precipitated simultaneously with the active catalyst. In the ion-exchange method, for example, highly dispersed Pt on... 

The usual preparation of supported micrycrystalline samples by the incipient wetness technique involves the impregnation of a support, e.g., silica gel or alumina, with a solution of a metal salt to form a thick slurry that is subsequently dried and sometimes heat-treated. 

From Na and Other Inert Gases. Adsorption isotherms for PH3 in mixtures with Na at 293 K were determined on various types of silica gel, activated carbon, and zeolites [3]. The removal from inert gases can be achieved by contact with silica gels [4], zeolites [4, 5], or activated carbon impregnated with CH3CN, picric acid, or maleic acid [4]. The adsorption on activated carbon pretreated with iodine compounds and sulfates or nitrates of ammonium and metals was used in [6]. Cu- or Ag-modified molecular sieves [7] or a soda-lime bed, which may contain nitrite salts, were also used as adsorbents [8]. The removal of PH3 by an aqueous solution of LiCl and HCIO4 was mentioned [9]. Its removal by oxidative methods is described in Section 1.3.1.5.4, p. 222. 

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