Kieselguhr, origin

A special TLC material, kieselguhr, originated from diatomaceous earth which is thermally treated and granulated to a specific particle size (such as between 5 and 40 pm). Kieselguhr has an extremely low specific surface, 1-5 m /g, therefore it is inert. Similar materials are known under various trade names such as Celit, Filter Cel, Hyflo Super Cel etc. [431. 

Since cobalt on kieselguhr in one of the original Fischer-Tropsch catalysts (1-9), it appeared attractive to investigate the catalytic activity of cobalt complexes immobilized on polystyrene. Although there are many supported cobalt-based Fischer-Tropsch catalysts known (see, for example, references 18-21), no polystyrene-bound systems had been reported. During the course of our work 18% (22,60,61) and 20% (23) crosslinked analogs of CpCo(C0)2 were shown to exhibit limited catalytic activity but no CO reduction. A preliminary disclosure of our work has appeared (2)4). 

FrP 1242324(1961) CA 56, 2628(1962) [Permissible expls prepd by substituting reed meal, peat NaCl by Al silicates (perlite type), kieselguhr, or by substances, of volcanic origin and by expanded plastic materials]... 

Stonite. Blasting expl, originally manufd in Ger and later in Engl and the USA. It contained NG 68, kieselguhr 20, K nitrate 8, and woodmeal, 4% Refs 1) Daniel (1902), 739 2) Barnett... 

Dynamite was originally made by absorbing nitroglycerin into kieselguhr, a type of clay. Modern dynamite generally includes wood flour, ammonium nitrate, or sodium nitrate to absorb the nitroglycerin. Such a mixture is easy to handle and can be made to contain as much as 75% nitroglycerin and yet retain its solid form. 

Dynamite is not a single molecular compound but a mixture of explosive and nonexplosive materials formulated in cylindrical paper or cardboard cartridges for a number of different blasting applications. Originally Nobel simply absorbed NG into kieselguhr, an inert diatomaceous material, but later he replaced that with active ingredients—finely divided fuels and oxidizers called dopes. Thus, energy is derived not only from the NG, but also from the reaction of oxidizers such as sodium nitrate with the combustibles. 

Both Liq Air and Liq Oxygen expls contain porous combustible material as fuel. These fuels are generally contained in paper or cloth cartridges. Occasionally liq fuels such as petroleum are mixed with the porous solids eg, some of Linde s early compositions (Ref 1) contained kieselguhr mixed with petroleum. Carbonized cork was also used in early Liq Air Expls, although charcoal was the original absorbent. More recently, as liq air was replaced... 

These suggestions were tested experimentally by Wasteneys and Borsook (68), who found that a peptic hydrolysate of protein gave, in the presence of concentrated pepsin solution and emulsion droplets of benzene or benzaldehyde, appreciable synthesis of a complex, less soluble material. Without the oil drops, reaction was very much slower, as the data in Fig. 24 show. Emulsions of fats, however, were noncatalytic, and xylol, talc, kieselguhr and barium sulfate were but weakly effective in increasing the rate. If the original protein is only slightly degraded, the yield in the synthesis is independent of the presence of the catalyst, but. 

The quality of the kieselguhr (diatomaceous earth) is of importance for the behavior of the cobalt catalyst. Kieselguhr of different origin resulted in catalysts of different activity. Ruhrchemie therefore investigated the reasons for the different behavior and issued standards for kieselguhr. The preliminary thermal treatment should be carried out... 

Kieselguhr of the Japanese origin, "Shimalite brand" or on alumina with subsequent modification by (2J ,3J )-tartaric acid does not make it possible to attain a value of ee in excess of 54-68% from the hydrogenation of MAA, even in the presence of high metal contents on the support (see Harada et al. ). Similar ee values were also obtained when nickel was deposited on Ti02 ee of 70%) and Zr02 ee of 68%) at 90 bar hydrogen pressure and 20°C... 

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